Provided by: par_1.53.0-2_amd64 bug

NAME

       par - filter for reformatting paragraphs

SYNOPSIS

       par  [ help ] [ version ] [ Bopset ] [ Popset ] [ Qopset ] [ Wopset ] [ Zopset ] [ h[hang] ]
            [ p[prefix] ] [ r[repeat] ] [ s[suffix] ] [ T[Tab] ] [ w[width] ] [ b[body] ] [ c[cap] ] [ d[div] ]
            [ E[Err] ] [ e[expel] ] [ f[fit] ] [ g[guess] ] [ j[just] ] [ l[last] ] [ q[quote] ] [ R[Report] ]
            [ t[touch] ]

DESCRIPTION

       par  is a filter which copies its input to its output, changing all white characters (except newlines) to
       spaces, and reformatting each paragraph.  Paragraphs are separated  by  protected,  blank,  and  bodiless
       lines  (see  the TERMINOLOGY section for definitions), and optionally delimited by indentation (see the d
       option in the OPTIONS section).

       Each output paragraph is generated from the corresponding input paragraph as follows:

           1) An optional prefix and/or suffix is removed from each input line.

           2) The remainder is divided into words (separated by spaces).

           3) The words are joined into lines to make an eye-pleasing paragraph.

           4) The prefixes and suffixes are reattached.

       If there are suffixes, spaces are inserted before them so that they all end in the same column.

QUICK START

       par is necessarily complex.  For those who wish to use it immediately and understand it later, assign the
       PARINIT environment variable the following value:

              rTbgqR B=.,?'_A_a_@ Q=_s>|

       The spaces, question mark, apostrophe, greater-than sign, and vertical  bar  will  probably  have  to  be
       escaped or quoted to prevent your shell from interpreting them.

       The  documentation, though precise, is unfortunately not well-written for the end-user.  Your best bet is
       probably to read quickly the DESCRIPTION, TERMINOLOGY,  OPTIONS,  and  ENVIRONMENT  sections,  then  read
       carefully the EXAMPLES section, referring back to the OPTIONS and TERMINOLOGY sections as needed.

       For  the  "power  user",  a  full understanding of par will require multiple readings of the TERMINOLOGY,
       OPTIONS, DETAILS, and EXAMPLES sections.

TERMINOLOGY

       Miscellaneous terms:

              charset syntax
                     A way of representing a set of characters as a string.   The  set  includes  exactly  those
                     characters  which  appear  in  the  string,  except  that  the  underscore (_) is an escape
                     character.  Whenever it appears, it must begin one of the following escape sequences:

                        __ = an underscore

                        _s = a space

                        _S = all space characters

                        _b = a backslash (\)

                        _q = a single quote (')

                        _Q = a double quote (")

                        _A = all upper case letters

                        _a = all lower case letters

                        _@ = all neither-case letters

                        _0 = all decimal digits

                      _xhh = the character represented by the two hexadecimal digits hh (which may be  upper  or
                             lower case)

                     The NUL character must not appear in the string, but it may be included in the set with the
                     _x00 sequence.

                     The  exact meanings of _S, _A, _a, _@, and _0 are locale-dependent.  (Actually, all locales
                     are supposed to agree on _0, but not on  the  others.)   In  the  default  "C"  locale:  _S
                     includes only space, formfeed, newline, carriage return, tab, and vertical tab; _A includes
                     only A through Z; _a includes only a through z; _@ includes nothing; and _0 includes only 0
                     through 9.

              error  A condition which causes par to abort.  See the DIAGNOSTICS section.

              IP     Input paragraph.

              OP     Output paragraph.

              parameter
                     A  symbol  which  may take on unsigned integral values.  There are several parameters whose
                     values affect the behavior of par.  Parameters can be assigned values  using  command  line
                     options.

       Types of characters:

              alphanumeric character
                     An alphabetic character or decimal digit, _A_a_@_0 in charset syntax (see above).

              body character
                     A  member  of  the  set  of characters defined by the PARBODY environment variable (see the
                     ENVIRONMENT section) and/or the B option (see the OPTIONS section).

              protective character
                     A member  of the set of characters defined by the PARPROTECT  environment  variable  and/or
                     the P option.

              quote character
                     A member of the set of characters defined by the PARQUOTE environment variable and/or the Q
                     option.

              terminal character
                     A member of the set of characters defined by the Z option.  Initially, before any Z options
                     have been processed, the set contains period, question mark, exclamation point, and colon.

              white character
                     A member of the set of characters defined by the W option.  Initially, before any W options
                     have  been  processed, the set contains space, formfeed, newline, carriage return, tab, and
                     vertical tab.

       Functions:

              comprelen
                     Given a non-empty sequence S of lines, let c  be  their  longest  common  prefix.   If  the
                     parameter  body  is  0, place a divider just after the leading non-body characters in c (at
                     the beginning if there are none).  If body is 1, place the divider just after the last non-
                     space non-body character in c (at the beginning if there is none), then advance the divider
                     over any immediately following spaces.  The comprelen of S  is  the  number  of  characters
                     preceding the divider.

              comsuflen
                     Given  a  non-empty  sequence S of lines, let p be the comprelen of S.  Let T be the set of
                     lines which result from stripping the first p characters from each line in S.  Let c be the
                     longest common suffix of the lines in T.  If body is 0, place a  divider  just  before  the
                     trailing  non-body characters in c (at the end if there are none), then advance the divider
                     over all but the last of any immediately following spaces.  If body is 1, place the divider
                     just before the first non-space non-body character, then  back  up  the  divider  over  one
                     immediately  preceding  space  if  there  is  one.   The  comsuflen  of  S is the number of
                     characters following the divider.

              fallback prelen (suflen)
                     The fallback prelen (suflen) of an IP is: the comprelen (comsuflen) of the IP,  if  the  IP
                     contains  at  least two lines; otherwise, the comprelen (comsuflen) of the block containing
                     the IP, if the block contains at least two lines; otherwise, the length of  the  longer  of
                     the  prefixes  (suffixes)  of  the  bodiless  lines  just above and below the block, if the
                     segment containing the block has any bodiless lines; otherwise,  0.   (See  below  for  the
                     definitions of block, segment, and bodiless line.)

              augmented fallback prelen
                     Let fp be the fallback prelen of an IP.  If the IP contains more than one line, or if quote
                     is  0, then the augmented fallback prelen of the IP is simply fp.  Otherwise, it is fp plus
                     the number of quote characters immediately following the first fp characters of the line.

              quoteprefix
                     The quoteprefix of a line is the longest  string  of  quote  characters  appearing  at  the
                     beginning of the line, after this string has been stripped of any trailing spaces.

       Types of lines:

              blank line
                     An  empty  line,  or a line whose first character is not protective and which contains only
                     spaces.

              protected line
                     An input line whose first character is protective.

              bodiless line
                     A line which is order k bodiless for some k.

              order k bodiless line
                     There is no such thing as  an  order  0  bodiless  line.   Suppose  S  is  a  a  contiguous
                     subsequence of a segment (see below) containing at least two lines, containing no order k-1
                     bodiless   lines,  bounded  above  and  below  by  order  k-1  bodiless  lines  and/or  the
                     beginning/end of the segment.  Let p and s be the comprelen and comsuflen of S.  Any member
                     of S which, if stripped of its first p and last s characters, would be blank  (or,  if  the
                     line  was  not  inserted  by the quote feature  and the parameter repeat is non-zero, would
                     consist of the same character repeated at least repeat times), is order  k  bodiless.   The
                     first p characters of the bodiless line comprise its prefix; the last s characters comprise
                     its  suffix.  The character which repeats in the middle is called its repeat character.  If
                     the middle is empty, the space is taken to be its repeat character.

              vacant line
                     A bodiless line whose repeat character is the space.

              superfluous line
                     Only blank and vacant lines may be superfluous.  If contiguous  vacant  lines  lie  at  the
                     beginning  or end of a segment, they are all superfluous.  But if they lie between two non-
                     vacant lines within a segment, then all are superfluous except one—the one  which  contains
                     the  fewest  non-spaces.   In  case  of  a  tie,  the  first  of  the tied lines is chosen.
                     Similarly, if contiguous blank lines lie outside of any segments at the beginning or end of
                     the input, they are all superfluous.  But if they lie between two segments and/or protected
                     lines, then all are superfluous except the first.

       Groups of lines:

              segment
                     A contiguous sequence of input lines containing no protected or blank lines, bounded  above
                     and below by protected lines, blank lines, and/or the beginning/end of the input.

              block  A contiguous subsequence of a segment containing no bodiless lines, bounded above and below
                     by bodiless lines and/or the beginning/end of the segment.

       Types of words:

              capitalized word
                     If  the  parameter  cap  is  0,  a  capitalized  word  is  one  which contains at least one
                     alphanumeric character, whose first alphanumeric character is not a lower case letter.   If
                     cap  is  1,  every word is considered a capitalized word.  (See the c option in the OPTIONS
                     section.)

              curious word
                     A word which contains a terminal character c such that there are no alphanumeric characters
                     in the word after c, but there is at least one alphanumeric character in the word before c.

OPTIONS

       Any command line argument may begin with one minus sign (-) which is ignored.  Generally, more  than  one
       option  may appear in a single command line argument, but there are exceptions:  The help, version, B, P,
       and Q options must have whole arguments all to themselves.

       help      Causes all remaining arguments to be ignored.  No input is read.  A usage message is printed on
                 the output briefly describing the options used by par.

       version   Causes all remaining arguments to be ignored.  No input  is  read.   "par  "  followed  by  its
                 version number is printed on the output.

       Bopset    op  is  a single character, either an equal sign (=), a plus sign (+), or a minus sign (-), and
                 set is a string using charset syntax.  If op is an equal sign, the set of  body  characters  is
                 set to the character set defined by set.  If op is a plus/minus sign, the characters in the set
                 defined  by  set  are  added/removed to/from the existing set of body characters defined by the
                 PARBODY environment variable and any previous B options.  It is okay to add characters that are
                 already in the set or to remove characters that are not in the set.

       Popset    Just like the B option, except that it applies to the set of protective characters.

       Qopset    Just like the B option, except that it applies to the set of quote characters.

       Wopset    Just like the B option, except that it applies to the set of white characters.

       Zopset    Just like the B option, except that it applies to the set of terminal characters.

       All remaining options are used to set values of parameters.  Values set by command line options hold  for
       all  paragraphs.   Unset parameters are given default values.  Any parameters whose default values depend
       on the IP (namely prefix and suffix), if left unset, are recomputed separately for each paragraph.

       The approximate role of each variable is described here.  See the DETAILS section for  the  rest  of  the
       story.

       The  first  six  parameters,  hang,  prefix,  repeat,  suffix, Tab, and width, may be set to any unsigned
       decimal integer less than 10000.

       h[hang]   Mainly affects the default values of prefix and suffix.  Defaults to 0.  If  the  h  option  is
                 given without a number, the value 1 is inferred.  (See also the p and s options.)

       p[prefix] The  first prefix characters of each line of the OP are copied from the first prefix characters
                 of the corresponding line of the IP.  If there are more  than  hang+1  lines  in  the  IP,  the
                 default  value  is  the  comprelen  of  all  the lines in the IP except the first hang of them.
                 Otherwise, the default value is the augmented fallback prelen of the IP.  If the  p  option  is
                 given  without a number, prefix is unset, even if it had been set earlier.  (See also the h and
                 q options.)

       r[repeat] If repeat is non-zero, bodiless lines have the number of instances of their  repeat  characters
                 increased  or  decreased  until  the  length  of  the line is width.  The exact value of repeat
                 affects the definition of bodiless line.  Defaults to 0.  If the r option is  given  without  a
                 number, the value 3 is inferred.  (See also the w option.)

       s[suffix] The last suffix characters of each line of the OP are copied from the last suffix characters of
                 the  corresponding  line of the IP.  If there are more than hang+1 lines in the IP, the default
                 value is the comsuflen of all the lines of the IP except the first hang  of  them.   Otherwise,
                 the default value is the fallback suflen of the IP.  If the s option is given without a number,
                 suffix is unset, even if it had been set earlier.  (See also the h option.)

       T[Tab]    Tab characters in the input are expanded to spaces, assuming tab stops every Tab columns.  Must
                 not be 0.  Defaults to 1.  If the T option is given without a number, the value 8 is inferred.

       w[width]  No  line in the OP may contain more than width characters, not including the trailing newlines.
                 Defaults to 72.  If the w option is given without a number, the value 79 is inferred.

       The remaining thirteen parameters, body, cap, div, Err, expel, fit,  guess,  invis,  just,  last,  quote,
       Report,  and  touch,  may be set to either 0 or 1.  If the number is absent in the option, the value 1 is
       inferred.

       b[body]   If body is 1, prefixes may not contain any trailing  body  characters,  and  suffixes  may  not
                 contain  any  leading  body  characters.   (Actually,  the  situation  is  complicated by space
                 characters.  See comprelen and comsuflen in the Terminology section.)  If body is  0,  prefixes
                 and suffixes may not contain any body characters at all.  Defaults to 0.

       c[cap]    If cap is 1, all words are considered capitalized.  This currently affects only the application
                 of the g option.  Defaults to 0.

       d[div]    If  div  is  0,  each  block  becomes an IP.  If div is 1, each block is subdivided into IPs as
                 follows:  Let p be the comprelen of the block.  Let  a  line's  status  be  1  if  its  (p+1)st
                 character  is  a  space,  0 otherwise.  Every line in the block whose status is the same as the
                 status of the first line will begin a new paragraph.  Defaults to 0.

       E[Err]    If Err is 1, messages to the user (caused by the help and version options, or  by  errors)  are
                 sent to the error stream instead of the output stream.  Defaults to 0.

       e[expel]  If expel is 1, superfluous lines are withheld from the output.  Defaults to 0.

       f[fit]    If  fit  is 1 and just is 0, par tries to make the lines in the OP as nearly the same length as
                 possible, even if it means making the OP narrower.  Defaults to 0.  (See also the j option.)

       g[guess]  If guess is 1, then when par is choosing line breaks, whenever it  encounters  a  curious  word
                 followed  by  a  capitalized  word,  it takes one of two special actions.  If the two words are
                 separated by a single space in the input, they will be merged into one word  with  an  embedded
                 non-breaking space.  If the two words are separated by more than one space, or by a line break,
                 par  will  insure  that  they  are  separated by two spaces, or by a line break, in the output.
                 Defaults to 0.

       i[invis]  If invis is 1, then vacant lines inserted because quote is 1 are invisible; that is,  they  are
                 not output.  If quote is 0, invis has no effect.  Defaults to 0.  (See also the q option.)

       j[just]   If  just is 1, par justifies the OP, inserting spaces between words so that all lines in the OP
                 have length width (except the last, if last is 0).  Defaults to 0.  (See also the w, l,  and  f
                 options.)

       l[last]   If  last  is  1, par tries to make the last line of the OP about the same length as the others.
                 Defaults to 0.

       q[quote]  If quote is 1, then before each segment is scanned for  bodiless  lines,  par  supplies  vacant
                 lines  between  different quotation nesting levels as follows:  For each pair of adjacent lines
                 in the segment, (scanned from the top down) which have  different  quoteprefixes,  one  of  two
                 actions  is  taken.   If  invis is 0, and either line consists entirely of quote characters and
                 spaces (or is empty), that line is truncated to the longest common  prefix  of  the  two  lines
                 (both  are  truncated  if  both  qualify).   Otherwise, a line consisting of the longest common
                 prefix of the two lines is inserted between them.  quote also  affects  the  default  value  of
                 prefix.  Defaults to 0.  (See also the p and i options.)

       R[Report] If  Report  is 1, it is considered an error for an input word to contain more than L = (width -
                 prefix - suffix) characters.  Otherwise, such words are chopped after each Lth  character  into
                 shorter words.  Defaults to 0.

       t[touch]  Has  no effect if suffix is 0 or just is 1.  Otherwise, if touch is 0, all lines in the OP have
                 length width.  If touch is 1, the length of the lines is decreased until the suffixes touch the
                 body of the OP.  Defaults to the logical OR of fit and last.  (See also the s, j, w, f,  and  l
                 options.)

       If  an  argument begins with a number, that number is assumed to belong to a p option if it is 8 or less,
       and to a w option otherwise.

       If the value of any parameter is set more than once, the last value is used.  When unset  parameters  are
       assigned  default values, hang and quote are assigned before prefix, and fit and last are assigned before
       touch (because of the dependencies).

       It is an error if width <= prefix + suffix.

ENVIRONMENT

       PARBODY   Determines the initial set of body characters (which are used for  determining  comprelens  and
                 comsuflens),  using  charset  syntax.   If  PARBODY  is  not set, the set of body characters is
                 initially empty.

       PARINIT   If set, par will read command line options from PARINIT before it reads them from  the  command
                 line.   Within  the  value  of  PARINIT,  arguments  are  separated by the initial set of white
                 characters.

       PARPROTECT
                 Determines the set of protective characters, using charset syntax.  If PARPROTECT is  not  set,
                 the set of protective characters is initially empty.

       PARQUOTE  Determines  the set of quote characters, using charset syntax.  If PARQUOTE is not set, the set
                 of quote characters initially contains only the greater-than sign (>) and the space.

       If a NUL character appears in the value of an environment variable, it and the rest of  the  string  will
       not be seen by par.

       Note  that  the  PARINIT  variable,  together with the B, P, and Q options, renders the other environment
       variables unnecessary.  They are included for backward compatibility.

DETAILS

       Lines are terminated by newline characters, but the newlines are not considered to  be  included  in  the
       lines.  If the last character of the input is a non-newline, a newline will be inferred immediately after
       it  (but if the input is empty, no newline will be inferred; the number of input lines will be 0).  Thus,
       the input can always be viewed as a sequence of lines.

       Protected lines are copied unchanged from the input to the output.  All other input lines,  as  they  are
       read,  have  any NUL characters removed, and every white character (except newlines) turned into a space.
       Actually, each tab character is turned into Tab - (n % Tab) spaces, where n is the number  of  characters
       preceding the tab character on the line (evaluated after earlier tab characters have been expanded).

       Blank lines in the input are transformed into empty lines in the output.

       If repeat is 0, all bodiless lines are vacant, and they are all simply stripped of trailing spaces before
       being  output.   If repeat is not 0, only vacant lines whose suffixes have length 0 are treated that way;
       other bodiless lines have the number of instances of their repeat characters increased or decreased until
       the length of the line is width.

       If expel is 1, superfluous lines are not output.  If quote and invis are both 1, there may  be  invisible
       lines; they are not output.

       The input is divided into segments, which are divided into blocks, which are divided into IPs.  The exact
       process  depends  on  the values of quote and div (see q and d in the OPTIONS section).  The remainder of
       this section describes  the  process  which  is  applied  independently  to  each  IP  to  construct  the
       corresponding OP.

       After  the values of the parameters are determined (see the OPTIONS section), the first prefix characters
       and the last suffix characters of each input line are removed and remembered.  It is  an  error  for  any
       line to contain fewer than prefix + suffix characters.

       The  remaining  text  is  treated as a sequence of characters, not lines.  The text is broken into words,
       which are separated by spaces.  That is, a word is a maximal sub-sequence of non-spaces.  If guess is  1,
       some  words  might  be  merged  (see  g in the OPTIONS section).  The first word includes any spaces that
       precede it on the same line.

       Let L = width - prefix - suffix.

       If Report is 0, some words may get chopped up at this point (see R in the OPTIONS section).

       The words are reassembled, preserving their order, into lines.  If just is 0,  adjacent  words  within  a
       line  are  separated  by  a single space, (or sometimes two if guess is 1), and line breaks are chosen so
       that the paragraph satisfies the following properties:

              1) No line contains more than L characters.

              2) If fit is 1, the difference between the lengths of the shortest and longest lines is  as  small
                 as possible.

              3) The shortest line is as long as possible, subject to properties 1 and 2.

              4) Let  target  be  L  if fit is 0, or the length of the longest line if fit is 1.  The sum of the
                 squares of the differences between target and the lengths of the lines is as small as possible,
                 subject to properties 1, 2, and 3.

            If last is 0, the last line does not count as a line for the purposes of  properties  2,  3,  and  4
            above.

            If  all  the  words  fit on a single line, the properties as worded above don't make much sense.  In
            that case, no line breaks are inserted.

       If just is 1, adjacent words within a line are separated by one space (or sometimes two if  guess  is  1)
       plus  zero or more extra spaces.  The value of fit is disregarded, and line breaks are chosen so that the
       paragraph satisfies the following properties:

              1) Every line contains exactly L characters.

              2) The largest inter-word gap is as small as possible, subject to property 1.  (An inter-word  gap
                 consists only of the extra spaces, not the regular spaces.)

              3) The  sum  of the squares of the lengths of the inter-word gaps is as small as possible, subject
                 to properties 1 and 2.

            If last is 0, the last line does not count as a line for the purposes of property 1, and it does not
            require or contain any extra spaces.

            Extra spaces are distributed as uniformly as possible among the inter-word gaps in each line.

            In a justified paragraph, every line must contain at least two words, but that's not always possible
            to accomplish.  If the paragraph cannot be justified, it is considered an error.

       If the number of lines in the resulting paragraph is less than hang, empty lines are added at the end  to
       bring the number of lines up to hang.

       If just is 0 and touch is 1, L is changed to be the length of the longest line.

       If suffix is not 0, each line is padded at the end with spaces to bring its length up to L.

       To  each  line  is  prepended  prefix characters.  Let n be the number of lines in the IP, let afp be the
       augmented fallback prelen of the IP, and let fs be the fallback suflen of the IP.  The  characters  which
       are prepended to the ith line are chosen as follows:

           1) If i <= n, the characters are copied from the ones that were removed from the beginning of the nth
              input line.

           2) If  i  > n > hang, the characters are copied from the ones that were removed from the beginning of
              the last input line.

           3) If i > n and n <= hang, the first min(afp,prefix) of the characters are copied from the ones  that
              were removed from the beginning of the last input line, and the rest are all spaces.

       Then  to  each line is appended suffix characters.  The characters which are appended to the ith line are
       chosen as follows:

           1) If i <= n, the characters are copied from the ones that were removed from the end of the nth input
              line.

           2) If i > n > hang, the characters are copied from the ones that were removed from  the  end  of  the
              last input line.

           3) If  i  > n and n <= hang, the first min(fs,suffix) of the characters are copied from the ones that
              were removed from the beginning of the last input line, and the rest are all spaces.

       Finally, the lines are printed to the output as the OP.

DIAGNOSTICS

       If there are no errors, par returns EXIT_SUCCESS (see <stdlib.h>).

       If there is an error, an error message will be printed to the output, and par will  return  EXIT_FAILURE.
       If  the  error  is local to a single paragraph, the preceding paragraphs will have been output before the
       error was detected.  Line numbers in error messages are local to the IP in which the error occurred.  All
       error messages begin with "par error:" on a line by itself.  Error messages concerning  command  line  or
       environment variable syntax are accompanied by the same usage message that the help option produces.

       Unless the option E is set, trying to print an error message would be futile if an error resulted from an
       output function, so par doesn't bother doing any error checking on output functions if E is 0.

EXAMPLES

       The  superiority  of par's dynamic programming algorithm over a greedy algorithm (such as the one used by
       fmt) can be seen in the following example:

       Original paragraph (note that each line begins with 8 spaces):

          We the people of the United States,
          in order to form a more perfect union,
          establish justice,
          insure domestic tranquility,
          provide for the common defense,
          promote the general welfare,
          and secure the blessing of liberty
          to ourselves and our posterity,
          do ordain and establish the Constitution
          of the United States of America.

       After a greedy algorithm with width = 39:

          We the people of the United
          States, in order to form a more
          perfect union, establish
          justice, insure domestic
          tranquility, provide for the
          common defense, promote the
          general welfare, and secure the
          blessing of liberty to
          ourselves and our posterity, do
          ordain and establish the
          Constitution of the United
          States of America.

       After "par 39":

          We the people of the United
          States, in order to form a
          more perfect union, establish
          justice, insure domestic
          tranquility, provide for the
          common defense, promote the
          general welfare, and secure
          the blessing of liberty to
          ourselves and our posterity,
          do ordain and establish the
          Constitution of the United
          States of America.

       The line breaks chosen by par are clearly more eye-pleasing.

       par is most useful in conjunction with the text-filtering features of an editor, such as the  !  commands
       of vi.  You may wish to add the following lines to your .exrc file:

          " use Bourne shell for speed:
          set shell=/bin/sh
          "
          " reformat paragraph with no arguments:
          map ** {!}par^M}
          "
          " reformat paragraph with arguments:
          map *^V  {!}par

       Note that the leading spaces must be removed, and that what is shown as ^M and ^V really need to be ctrl-
       M  and ctrl-V.  Also note that the last map command contains two spaces following the ctrl-V, plus one at
       the end of the line.

       To reformat a simple paragraph delimited by blank lines in vi, you can put the cursor anywhere in it  and
       type  "**"  (star  star). If you need to supply arguments to par, you can type "* " (star space) instead,
       then type the arguments.

       The rest of this section is a series of before-and-after pictures showing some typical uses of  par.   In
       all cases, no environment variables are set.

       Before:

          /*   We the people of the United States, */
          /* in order to form a more perfect union, */
          /* establish justice, */
          /* insure domestic tranquility, */
          /* provide for the common defense, */
          /* promote the general welfare, */
          /* and secure the blessing of liberty */
          /* to ourselves and our posterity, */
          /* do ordain and establish the Constitution */
          /* of the United States of America. */

       After "par 59":

          /*   We the people of the United States, in      */
          /* order to form a more perfect union, establish */
          /* justice, insure domestic tranquility, provide */
          /* for the common defense, promote the general   */
          /* welfare, and secure the blessing of liberty   */
          /* to ourselves and our posterity, do ordain     */
          /* and establish the Constitution of the United  */
          /* States of America.                            */

       Or after "par 59f":

          /*   We the people of the United States,  */
          /* in order to form a more perfect union, */
          /* establish justice, insure domestic     */
          /* tranquility, provide for the common    */
          /* defense, promote the general welfare,  */
          /* and secure the blessing of liberty to  */
          /* ourselves and our posterity, do ordain */
          /* and establish the Constitution of the  */
          /* United States of America.              */

       Or after "par 59l":

          /*   We the people of the United States, in      */
          /* order to form a more perfect union, establish */
          /* justice, insure domestic tranquility,         */
          /* provide for the common defense, promote       */
          /* the general welfare, and secure the           */
          /* blessing of liberty to ourselves and our      */
          /* posterity, do ordain and establish the        */
          /* Constitution of the United States of America. */

       Or after "par 59lf":

          /*   We the people of the United States,  */
          /* in order to form a more perfect union, */
          /* establish justice, insure domestic     */
          /* tranquility, provide for the common    */
          /* defense, promote the general welfare,  */
          /* and secure the blessing of liberty     */
          /* to ourselves and our posterity, do     */
          /* ordain and establish the Constitution  */
          /* of the United States of America.       */

       Or after "par 59lft0":

          /*   We the people of the United States,         */
          /* in order to form a more perfect union,        */
          /* establish justice, insure domestic            */
          /* tranquility, provide for the common           */
          /* defense, promote the general welfare,         */
          /* and secure the blessing of liberty            */
          /* to ourselves and our posterity, do            */
          /* ordain and establish the Constitution         */
          /* of the United States of America.              */

       Or after "par 59j":

          /*   We  the people  of  the  United States,  in */
          /* order to form a more perfect union, establish */
          /* justice, insure domestic tranquility, provide */
          /* for the  common defense, promote  the general */
          /* welfare, and  secure the blessing  of liberty */
          /* to ourselves and our posterity, do ordain and */
          /* establish  the  Constitution  of  the  United */
          /* States of America.                            */

       Or after "par 59jl":

          /*   We  the   people  of  the   United  States, */
          /* in   order    to   form   a    more   perfect */
          /* union,  establish  justice,  insure  domestic */
          /* tranquility, provide for  the common defense, */
          /* promote  the  general   welfare,  and  secure */
          /* the  blessing  of  liberty to  ourselves  and */
          /* our  posterity, do  ordain and  establish the */
          /* Constitution of the United States of America. */

       Before:

          Preamble      We the people of the United States,
          to the US     in order to form
          Constitution  a more perfect union,
                        establish justice,
                        insure domestic tranquility,
                        provide for the common defense,
                        promote the general welfare,
                        and secure the blessing of liberty
                        to ourselves and our posterity,
                        do ordain and establish
                        the Constitution
                        of the United States of America.

       After "par 52h3":

          Preamble      We the people of the United
          to the US     States, in order to form a
          Constitution  more perfect union, establish
                        justice, insure domestic
                        tranquility, provide for the
                        common defense, promote the
                        general welfare, and secure
                        the blessing of liberty to
                        ourselves and our posterity,
                        do ordain and establish the
                        Constitution of the United
                        States of America.

       Before:

           1  We the people of the United States,
           2  in order to form a more perfect union,
           3  establish justice,
           4  insure domestic tranquility,
           5  provide for the common defense,
           6  promote the general welfare,
           7  and secure the blessing of liberty
           8  to ourselves and our posterity,
           9  do ordain and establish the Constitution
          10  of the United States of America.

       After "par 59p12l":

           1  We the people of the United States, in order to
           2  form a more perfect union, establish justice,
           3  insure domestic tranquility, provide for the
           4  common defense, promote the general welfare,
           5  and secure the blessing of liberty to ourselves
           6  and our posterity, do ordain and establish the
           7  Constitution of the United States of America.

       Before:

          > > We the people
          > > of the United States,
          > > in order to form a more perfect union,
          > > establish justice,
          > > ensure domestic tranquility,
          > > provide for the common defense,
          >
          > Promote the general welfare,
          > and secure the blessing of liberty
          > to ourselves and our posterity,
          > do ordain and establish
          > the Constitution of the United States of America.

       After "par 52":

          > > We the people of the United States, in
          > > order to form a more perfect union,
          > > establish justice, ensure domestic
          > > tranquility, provide for the common
          > > defense,
          >
          > Promote the general welfare, and secure
          > the blessing of liberty to ourselves and
          > our posterity, do ordain and establish
          > the Constitution of the United States of
          > America.

       Before:

          >   We the people
          > of the United States,
          > in order to form a more perfect union,
          > establish justice,
          > ensure domestic tranquility,
          > provide for the common defense,
          >   Promote the general welfare,
          > and secure the blessing of liberty
          > to ourselves and our posterity,
          > do ordain and establish
          > the Constitution of the United States of America.

       After "par 52d":

          >   We the people of the United States,
          > in order to form a more perfect union,
          > establish justice, ensure domestic
          > tranquility, provide for the common
          > defense,
          >   Promote the general welfare, and secure
          > the blessing of liberty to ourselves and
          > our posterity, do ordain and establish
          > the Constitution of the United States of
          > America.

       Before:

          # 1. We the people of the United States.
          # 2. In order to form a more perfect union.
          # 3. Establish justice, ensure domestic
          #    tranquility.
          # 4. Provide for the common defense
          # 5. Promote the general welfare.
          # 6. And secure the blessing of liberty
          #    to ourselves and our posterity.
          # 7. Do ordain and establish the Constitution.
          # 8. Of the United States of America.

       After "par 37p13dh":

          # 1. We the people of the
          #    United States.
          # 2. In order to form a more
          #    perfect union.
          # 3. Establish justice,
          #    ensure domestic
          #    tranquility.
          # 4. Provide for the common
          #    defense
          # 5. Promote the general
          #    welfare.
          # 6. And secure the blessing
          #    of liberty to ourselves
          #    and our posterity.
          # 7. Do ordain and establish
          #    the Constitution.
          # 8. Of the United States of
          #    America.

       Before:

          /*****************************************/
          /*   We the people of the United States, */
          /* in order to form a more perfect union, */
          /* establish justice, insure domestic    */
          /* tranquility,                          */
          /*                                       */
          /*                                       */
          /*   [ provide for the common defense, ] */
          /*   [ promote the general welfare,    ] */
          /*   [ and secure the blessing of liberty ] */
          /*   [ to ourselves and our posterity, ] */
          /*   [                                 ] */
          /*                                       */
          /* do ordain and establish the Constitution */
          /* of the United States of America.       */
          /******************************************/

       After "par 42r":

          /********************************/
          /*   We the people of the       */
          /* United States, in order to   */
          /* form a more perfect union,   */
          /* establish justice, insure    */
          /* domestic tranquility,        */
          /*                              */
          /*                              */
          /*   [ provide for the common ] */
          /*   [ defense, promote the   ] */
          /*   [ general welfare, and   ] */
          /*   [ secure the blessing of ] */
          /*   [ liberty to ourselves   ] */
          /*   [ and our posterity,     ] */
          /*   [                        ] */
          /*                              */
          /* do ordain and establish the  */
          /* Constitution of the United   */
          /* States of America.           */
          /********************************/

       Or after "par 42re":

          /********************************/
          /*   We the people of the       */
          /* United States, in order to   */
          /* form a more perfect union,   */
          /* establish justice, insure    */
          /* domestic tranquility,        */
          /*                              */
          /*   [ provide for the common ] */
          /*   [ defense, promote the   ] */
          /*   [ general welfare, and   ] */
          /*   [ secure the blessing of ] */
          /*   [ liberty to ourselves   ] */
          /*   [ and our posterity,     ] */
          /*                              */
          /* do ordain and establish the  */
          /* Constitution of the United   */
          /* States of America.           */
          /********************************/

       Before:

          Joe Public writes:
          > Jane Doe writes:
          > >
          > >
          > > I can't find the source for uncompress.
          > Oh no, not again!!!
          >
          >
          > Isn't there a FAQ for this?
          >
          >
          That wasn't very helpful, Joe. Jane,
          just make a link from uncompress to compress.

       After "par 40q":

          Joe Public writes:

          > Jane Doe writes:
          >
          >
          > > I can't find the source for
          > > uncompress.
          >
          > Oh no, not again!!!
          >
          >
          > Isn't there a FAQ for this?
          >

          That wasn't very helpful, Joe.
          Jane, just make a link from
          uncompress to compress.

       Or after "par 40qe":

          Joe Public writes:

          > Jane Doe writes:
          >
          > > I can't find the source for
          > > uncompress.
          >
          > Oh no, not again!!!
          >
          > Isn't there a FAQ for this?

          That wasn't very helpful, Joe.
          Jane, just make a link from
          uncompress to compress.

       Or after "par 40qi":

          Joe Public writes:
          > Jane Doe writes:
          > >
          > >
          > > I can't find the source for
          > > uncompress.
          > Oh no, not again!!!
          >
          >
          > Isn't there a FAQ for this?
          >
          >
          That wasn't very helpful, Joe.
          Jane, just make a link from
          uncompress to compress.

       Or after "par 40qie":

          Joe Public writes:
          > Jane Doe writes:
          > > I can't find the source for
          > > uncompress.
          > Oh no, not again!!!
          >
          > Isn't there a FAQ for this?
          That wasn't very helpful, Joe.
          Jane, just make a link from
          uncompress to compress.

       Before:

          I sure hope there's still room
          in Dr. Jones' section of archaeology.
          I've heard he's the bestest.  [sic]

       After "par 50g":

          I sure hope there's still room in
          Dr. Jones' section of archaeology.  I've
          heard he's the bestest. [sic]

       Or after "par 50gc":

          I sure hope there's still room in
          Dr. Jones' section of archaeology.  I've
          heard he's the bestest.  [sic]

       Before:

          John writes:
          : Mary writes:
          : + Anastasia writes:
          : + > Hi all!
          : + Hi Ana!
          : Hi Ana & Mary!
          Please unsubscribe me from alt.hello.

       After "par Q+:+ q":

          John writes:

          : Mary writes:
          :
          : + Anastasia writes:
          : +
          : + > Hi all!
          : +
          : + Hi Ana!
          :
          : Hi Ana & Mary!

          Please unsubscribe me from alt.hello.

       Before:

          amc> The b option was added primarily to deal with
          amc> this new style of quotation
          amc> which became popular after Par 1.41 was released.
          amc>
          amc> Par still pays attention to body characters.
          amc> Par should not mistake "Par" for part of the prefix.
          amc> Par should not mistake "." for a suffix.

       After "par B=._A_a 50bg":

          amc> The b option was added primarily to
          amc> deal with this new style of quotation
          amc> which became popular after Par 1.41
          amc> was released.
          amc>
          amc> Par still pays attention to body
          amc> characters.  Par should not mistake
          amc> "Par" for part of the prefix.  Par
          amc> should not mistake "." for a suffix.

SEE ALSO

       par.doc

LIMITATIONS

       The guess feature guesses wrong in cases like the following:

          I calc'd the approx.
          Fermi level to 3 sig. digits.

       With guess = 1, par will incorrectly assume that "approx."  ends a sentence.  If the input were:

          I calc'd the approx. Fermi
          level to 3 sig. digits.

       then  par  would  refuse to put a line break between "approx." and "Fermi" in the output, mainly to avoid
       creating the first situation (in case the paragraph were to be fed back through par  again).   This  non-
       breaking space policy does come in handy for cases like "Mr. Johnson" and "Jan. 1", though.

       The  guess  feature  only  goes one way.  par can preserve wide sentence breaks in a paragraph, or remove
       them, but it can't insert them if they aren't already in the input.

       If you use tabs, you may not like the way par handles (or doesn't handle) them.   It  expands  them  into
       spaces.   I  didn't  let  par output tabs because tabs don't make sense.  Not everyone's terminal has the
       same tab settings, so text files containing tabs are sometimes mangled.  In fact, almost every text  file
       containing  tabs  gets  mangled when something is inserted at the beginning of each line (when quoting e-
       mail or commenting out a section of a shell script, for example), making them a  pain  to  edit.   In  my
       opinion,  the  world  would  be a nicer place if everyone stopped using tabs, so I'm doing my part by not
       letting par output them.  (Thanks to Eric Stuebe for showing me the light about tabs.)

       There is currently no way for the length of the output prefix to differ from  the  length  of  the  input
       prefix.   Ditto for the suffix.  I may consider adding this capability in a future release, but right now
       I'm not sure how I'd want it to work.

APOLOGIES

       Par began in July 1993 as a small program designed to do one narrow task:  reformat  a  single  paragraph
       that  might have a border on either side.  It was pretty clean back then.  Over the next three months, it
       very rapidly expanded to handle multiple paragraphs, offer more options, and take better guesses, at  the
       cost  of  becoming  extremely  complex,  and very unclean.  It is nowhere near the optimal design for the
       larger task it now tries to address.  Its only redeeming features are that it is extremely useful (I find
       it indispensable), extremely portable, and very stable since version 1.41 released on 1993-Oct-31.

       Back in 1993 I had very little experience at writing documentation for users, so  the  documentation  for
       Par  became rather nightmarish.  There is no separation between how-it-works (which is painfully complex)
       and how-to-use-it (which is fairly simple, if you can ever figure it out).

       Someday I ought to reexamine the problem, and redesign a new, clean solution from scratch.  I don't  know
       when I might get enough free time to start on such a project.  Text files may be obsolete by then.

BUGS

       If  I  knew of any bugs, I wouldn't release the package.  Of course, there may be bugs that I haven't yet
       discovered.

       If you find any bugs (in the program or in the documentation), or if you  have  any  suggestions,  please
       contact me:

              http://www.nicemice.net/amc/

       When  reporting  a  bug,  please  include  the exact input and command line options used, and the version
       number of par, so that I can reproduce it.

       The latest release of Par is available on the Web at:

              http://www.nicemice.net/par/

       I don't expect these URLs to change in the forseeable future, but if they do, I'll try to  leave  forward
       pointers.

Par 1.53.0                                         2020-Mar-14                                            par(1)