Provided by: txt2html_3.0-1_all 
NAME
HTML::TextToHTML - convert plain text file to HTML.
VERSION
version 3.0
SYNOPSIS
From the command line:
txt2html I<arguments>
From Scripts:
use HTML::TextToHTML;
# create a new object
my $conv = new HTML::TextToHTML();
# convert a file
$conv->txt2html(infile=>[$text_file],
outfile=>$html_file,
title=>"Wonderful Things",
mail=>1,
]);
# reset arguments
$conv->args(infile=>[], mail=>0);
# convert a string
$newstring = $conv->process_chunk($mystring)
DESCRIPTION
HTML::TextToHTML converts plain text files to HTML. The txt2html script uses this module to do the same
from the command-line.
It supports headings, tables, lists, simple character markup, and hyperlinking, and is highly
customizable. It recognizes some of the apparent structure of the source document (mostly whitespace and
typographic layout), and attempts to mark that structure explicitly using HTML. The purpose for this tool
is to provide an easier way of converting existing text documents to HTML format, giving something nicer
than just whapping the text into a big PRE block.
History
The original txt2html script was written by Seth Golub (see http://www.aigeek.com/txt2html/), and
converted to a perl module by Kathryn Andersen (see http://www.katspace.com/tools/text_to_html/) and made
into a sourceforge project by Sun Tong (see http://sourceforge.net/projects/txt2html/). Earlier versions
of the HTML::TextToHTML module called the included script texthyper so as not to clash with the original
txt2html script, but now the projects have all been merged. UPDATING: currently, the project is available
on GitHub at https://github.com/resurrecting-open-source-projects/txt2html
OPTIONS
All arguments can be set when the object is created, and further options can be set when calling the
actual txt2html method. Arguments to methods can take a hash of arguments.
Note that all option-names must match exactly -- no abbreviations are allowed. The argument-keys are
expected to have values matching those required for that argument -- whether that be a boolean, a string,
a reference to an array or a reference to a hash. These will replace any value for that argument that
might have been there before.
append_file
append_file=>I<filename>
If you want something appended by default, put the filename here. The appended text will not be
processed at all, so make sure it's plain text or correct HTML. i.e. do not have things like:
Mary Andersen <kitty@example.com> but instead, have:
Mary Andersen <kitty@example.com>
(default: nothing)
append_head
append_head=>I<filename>
If you want something appended to the head by default, put the filename here. The appended text will
not be processed at all, so make sure it's plain text or correct HTML. i.e. do not have things like:
Mary Andersen <kitty@example.com> but instead, have:
Mary Andersen <kitty@example.com>
(default: nothing)
body_deco
body_deco=>I<string>
Body decoration string: a string to be added to the BODY tag so that one can set attributes to the
BODY (such as class, style, bgcolor etc) For example, "class='withimage'".
bold_delimiter
bold_delimiter=>I<string>
This defines what character (or string) is taken to be the delimiter of text which is to be
interpreted as bold (that is, to be given a STRONG tag). If this is empty, then no bolding of text
will be done. (default: #)
bullets
bullets=>I<string>
This defines what single characters are taken to be "bullet" characters for unordered lists. Note
that because this is used as a character class, if you use '-' it must come first.
(default:-=o*\267)
bullets_ordered
bullets_ordered=>I<string>
This defines what single characters are taken to be "bullet" placeholder characters for ordered
lists. Ordered lists are normally marked by a number or letter followed by '.' or ')' or ']' or ':'.
If an ordered bullet is used, then it simply indicates that this is an ordered list, without giving
explicit numbers.
Note that because this is used as a character class, if you use '-' it must come first.
(default:nothing)
caps_tag
caps_tag=>I<tag>
Tag to put around all-caps lines (default: STRONG) If an empty tag is given, then no tag will be put
around all-caps lines.
custom_heading_regexp
custom_heading_regexp=>\@custom_headings
Add patterns for headings. Header levels are assigned by regexp in the order seen in the input text.
When a line matches a custom header regexp, it is tagged as a header. If it's the first time that
particular regexp has matched, the next available header level is associated with it and applied to
the line. Any later matches of that regexp will use the same header level. Therefore, if you want
to match numbered header lines, you could use something like this:
my @custom_headings = ('^ *\d+\. \w+',
'^ *\d+\.\d+\. \w+',
'^ *\d+\.\d+\.\d+\. \w+');
...
custom_heading_regexp=>\@custom_headings,
...
Then lines like
" 1. Examples "
" 1.1. Things"
and " 4.2.5. Cold Fusion"
Would be marked as H1, H2, and H3 (assuming they were found in that order, and that no other header
styles were encountered). If you prefer that the first one specified always be H1, the second always
be H2, the third H3, etc, then use the "explicit_headings" option.
This expects a reference to an array of strings.
(default: none)
default_link_dict
default_link_dict=>I<filename>
The name of the default "user" link dictionary. (default: "$ENV{'HOME'}/.txt2html.dict" -- this is
the same as for the txt2html script. If there is no $ENV{HOME} then it is just '.txt2html.dict')
demoronize
demoronize=>1
Convert Microsoft-generated character codes that are non-ISO codes into something more reasonable.
(default:true)
doctype
doctype=>I<doctype>
This gets put in the DOCTYPE field at the top of the document, unless it's empty.
Default : '-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd'
If xhtml is true, the contents of this is ignored, unless it's empty, in which case no DOCTYPE
declaration is output.
eight_bit_clean
eight_bit_clean=>1
If false, convert Latin-1 characters to HTML entities. If true, this conversion is disabled; also
"demoronize" is set to false, since this also changes 8-bit characters. (default: false)
escape_HTML_chars
escape_HTML_chars=>1
turn & < > into & > < (default: true)
explicit_headings
explicit_headings=>1
Don't try to find any headings except the ones specified in the --custom_heading_regexp option.
Also, the custom headings will not be assigned levels in the order they are encountered in the
document, but in the order they are specified on the custom_heading_regexp option. (default: false)
extract
extract=>1
Extract Mode; don't put HTML headers or footers on the result, just the plain HTML (thus making the
result suitable for inserting into another document (or as part of the output of a CGI script).
(default: false)
hrule_min
hrule_min=>I<n>
Min number of ---s for an HRule. (default: 4)
indent_width
indent_width=>I<n>
Indents this many spaces for each level of a list. (default: 2)
indent_par_break
indent_par_break=>1
Treat paragraphs marked solely by indents as breaks with indents. That is, instead of taking a
three-space indent as a new paragraph, put in a <BR> and three non-breaking spaces instead. (see
also --preserve_indent) (default: false)
infile
infile=>\@my_files
infile=>['chapter1.txt', 'chapter2.txt']
The name of the input file(s). This expects a reference to an array of filenames.
The special filename '-' designates STDIN.
See also "inhandle" and "instring".
(default:-)
inhandle
inhandle=>\@my_handles
inhandle=>[\*MYINHANDLE, \*STDIN]
An array of input filehandles; use this instead of "infile" or "instring" to use a filehandle or
filehandles as input.
instring
instring=>\@my_strings
instring=>[$string1, $string2]
An array of input strings; use this instead of "infile" or "inhandle" to use a string or strings as
input.
italic_delimiter
italic_delimiter=>I<string>
This defines what character (or string) is taken to be the delimiter of text which is to be
interpreted as italic (that is, to be given a EM tag). If this is empty, no italicising of text will
be done. (default: *)
underline_delimiter
underline_delimiter=>I<string>
This defines what character (or string) is taken to be the delimiter of text which is to be
interpreted as underlined (that is, to be given a U tag). If this is empty, no underlining of text
will be done. (default: _)
links_dictionaries
links_dictionaries=>\@my_link_dicts
links_dictionaries=>['url_links.dict', 'format_links.dict']
File(s) to use as a link-dictionary. There can be more than one of these. These are in addition to
the Global Link Dictionary and the User Link Dictionary. This expects a reference to an array of
filenames.
link_only
link_only=>1
Do no escaping or marking up at all, except for processing the links dictionary file and applying it.
This is useful if you want to use the linking feature on an HTML document. If the HTML is a complete
document (includes HTML,HEAD,BODY tags, etc) then you'll probably want to use the --extract option
also. (default: false)
lower_case_tags
lower_case_tags=>1
Force all tags to be in lower-case.
mailmode
mailmode=>1
Deal with mail headers & quoted text. The mail header paragraph is given the class 'mail_header',
and mail-quoted text is given the class 'quote_mail'. (default: false)
make_anchors
make_anchors=>0
Should we try to make anchors in headings? (default: true)
make_links
make_links=>0
Should we try to build links? If this is false, then the links dictionaries are not consulted and
only structural text-to-HTML conversion is done. (default: true)
make_tables
make_tables=>1
Should we try to build tables? If true, spots tables and marks them up appropriately. See "Input
File Format" for information on how tables should be formatted.
This overrides the detection of lists; if something looks like a table, it is taken as a table, and
list-checking is not done for that paragraph.
(default: false)
min_caps_length
min_caps_length=>I<n>
min sequential CAPS for an all-caps line (default: 3)
outfile
outfile=>I<filename>
The name of the output file. If it is "-" then the output goes to Standard Output. (default: - )
outhandle
The output filehandle; if this is given then the output goes to this filehandle instead of to the
file given in "outfile".
par_indent
par_indent=>I<n>
Minimum number of spaces indented in first lines of paragraphs.
Only used when there's no blank line preceding the new paragraph. (default: 2)
preformat_trigger_lines
preformat_trigger_lines=>I<n>
How many lines of preformatted-looking text are needed to switch to <PRE>
<= 0 : Preformat entire document
1 : one line triggers
>= 2 : two lines trigger
(default: 2)
endpreformat_trigger_lines
endpreformat_trigger_lines=>I<n>
How many lines of unpreformatted-looking text are needed to switch from <PRE>
<= 0 : Never preformat within document
1 : one line triggers
>= 2 : two lines trigger (default: 2)
NOTE for preformat_trigger_lines and endpreformat_trigger_lines: A zero takes precedence. If one is
zero, the other is ignored. If both are zero, entire document is preformatted.
preformat_start_marker
preformat_start_marker=>I<regexp>
What flags the start of a preformatted section if --use_preformat_marker is true.
(default: "^(:?(:?<)|<)PRE(:?(:?>)|>)\$")
preformat_end_marker
preformat_end_marker=>I<regexp>
What flags the end of a preformatted section if --use_preformat_marker is true.
(default: "^(:?(:?<)|<)/PRE(:?(:?>)|>)\$")
preformat_whitespace_min
preformat_whitespace_min=>I<n>
Minimum number of consecutive whitespace characters to trigger normal preformatting. NOTE: Tabs are
expanded to spaces before this check is made. That means if tab_width is 8 and this is 5, then one
tab may be expanded to 8 spaces, which is enough to trigger preformatting. (default: 5)
prepend_file
prepend_file=>I<filename>
If you want something prepended to the processed body text, put the filename here. The prepended
text will not be processed at all, so make sure it's plain text or correct HTML.
(default: nothing)
preserve_indent
preserve_indent=>1
Preserve the first-line indentation of paragraphs marked with indents by replacing the spaces of the
first line with non-breaking spaces. (default: false)
short_line_length
short_line_length=>I<n>
Lines this short (or shorter) must be intentionally broken and are kept that short. (default: 40)
style_url
style_url=>I<url>
This gives the URL of a stylesheet; a LINK tag will be added to the output.
tab_width
tab_width=>I<n>
How many spaces equal a tab? (default: 8)
table_type
table_type=>{ ALIGN=>0, PGSQL=>0, BORDER=>1, DELIM=>0 }
This determines which types of tables will be recognised when "make_tables" is true. The possible
types are ALIGN, PGSQL, BORDER and DELIM. (default: all types are true)
title
title=>I<title>
You can specify a title. Otherwise it will use a blank one. (default: nothing)
titlefirst
titlefirst=>1
Use the first non-blank line as the title. (See also "title")
underline_length_tolerance
underline_length_tolerance=>I<n>
How much longer or shorter can underlines be and still be underlines? (default: 1)
underline_offset_tolerance
underline_offset_tolerance=>I<n>
How far offset can underlines be and still be underlines? (default: 1)
unhyphenation
unhyphenation=>0
Enables unhyphenation of text. (default: true)
use_mosaic_header
use_mosaic_header=>1
Use this option if you want to force the heading styles to match what Mosaic outputs. (Underlined
with "***"s is H1, with "==="s is H2, with "+++" is H3, with "---" is H4, with "~~~" is H5 and with
"..." is H6) This was the behavior of txt2html up to version 1.10. (default: false)
use_preformat_marker
use_preformat_marker=>1
Turn on preformatting when encountering "<PRE>" on a line by itself, and turn it off when there's a
line containing only "</PRE>". When such preformatted text is detected, the PRE tag will be given
the class 'quote_explicit'. (default: off)
xhtml
xhtml=>1
Try to make the output conform to the XHTML standard, including closing all open tags and marking
empty tags correctly. This turns on --lower_case_tags and overrides the --doctype option. Note that
if you add a header or a footer file, it is up to you to make it conform; the header/footer isn't
touched by this. Likewise, if you make link-dictionary entries that break XHTML, then this won't fix
them, except to the degree of putting all tags into lower-case.
(default: true)
DEBUGGING
There are global variables for setting types and levels of debugging. These should only be used by
developers.
$HTML::TextToHTML::Debug
$HTML::TextToHTML::Debug = 1;
Enable copious debugging output. (default: false)
$HTML::TextToHTML::DictDebug
$HTML::TextToHTML::DictDebug = I<n>;
Debug mode for link dictionaries. Bitwise-Or what you want to see:
1: The parsing of the dictionary
2: The code that will make the links
4: When each rule matches something
8: When each tag is created
(default: 0)
METHODS
new
$conv = new HTML::TextToHTML()
$conv = new HTML::TextToHTML(titlefirst=>1,
...
);
Create a new object with new. If arguments are given, these arguments will be used in invocations of
other methods.
See "OPTIONS" for the possible values of the arguments.
args
$conv->args(short_line_length=>60,
titlefirst=>1,
....
);
Updates the current arguments/options of the HTML::TextToHTML object. Takes hash of arguments, which
will be used in invocations of other methods. See "OPTIONS" for the possible values of the arguments.
process_chunk
$newstring = $conv->process_chunk($mystring);
Convert a string to a HTML fragment. This assumes that this string is at the least, a single paragraph,
but it can contain more than that. This returns the processed string. If you want to pass arguments to
alter the behaviour of this conversion, you need to do that earlier, either when you create the object,
or with the "args" method.
$newstring = $conv->process_chunk($mystring,
close_tags=>0);
If there are open tags (such as lists) in the input string, process_chunk will automatically close them,
unless you specify not to, with the close_tags option.
$newstring = $conv->process_chunk($mystring,
is_fragment=>1);
If you want this string to be treated as a fragment, and not assumed to be a paragraph, set is_fragment
to true. If there is more than one paragraph in the string (ie it contains blank lines) then this option
will be ignored.
process_para
$newstring = $conv->process_para($mystring);
Convert a string to a HTML fragment. This assumes that this string is at the most a single paragraph,
with no blank lines in it. If you don't know whether your string will contain blank lines or not, use
the "process_chunk" method instead.
This returns the processed string. If you want to pass arguments to alter the behaviour of this
conversion, you need to do that earlier, either when you create the object, or with the "args" method.
$newstring = $conv->process_para($mystring,
close_tags=>0);
If there are open tags (such as lists) in the input string, process_para will automatically close them,
unless you specify not to, with the close_tags option.
$newstring = $conv->process_para($mystring,
is_fragment=>1);
If you want this string to be treated as a fragment, and not assumed to be a paragraph, set is_fragment
to true.
txt2html
$conv->txt2html(%args);
Convert a text file to HTML. Takes a hash of arguments. See "OPTIONS" for the possible values of the
arguments. Arguments which have already been set with new or args will remain as they are, unless they
are overridden.
PRIVATE METHODS
These are methods used internally, only of interest to developers.
init_our_data
$self->init_our_data();
Initializes the internal object data.
deal_with_options
$self->deal_with_options();
do extra processing related to particular options
escape
$newtext = escape($text);
Escape & < and >
demoronize_char
$newtext = demoronize_char($text);
Convert Microsoft character entities into characters.
Added by Alan Jackson, alan at ajackson dot org, and based on the demoronize script by John Walker,
http://www.fourmilab.ch/
demoronize_code
$newtext = demoronize_code($text);
convert Microsoft character entities into HTML code
get_tag
$tag = $self->get_tag($in_tag);
$tag = $self->get_tag($in_tag, tag_type=>TAG_START, inside_tag=>'');
output the tag wanted (add the <> and the / if necessary) - output in lower or upper case - do tag-
related processing options:
tag_type=>TAG_START | tag_type=>TAG_END | tag_type=>TAG_EMPTY
(default start)
inside_tag=>string (default empty)
close_tag
$tag = $self->close_tag($in_tag);
close the open tag
hrule
$self->hrule(para_lines_ref=>$para_lines,
para_action_ref=>$para_action,
ind=>0);
Deal with horizontal rules.
shortline
$self->shortline(line_ref=>$line_ref,
line_action_ref=>$line_action_ref,
prev_ref=>$prev_ref,
prev_action_ref=>$prev_action_ref,
prev_line_len=>$prev_line_len);
Deal with short lines.
is_mailheader
if ($self->is_mailheader(rows_ref=>$rows_ref))
{
...
}
Is this a mailheader line?
mailheader
$self->mailheader(rows_ref=>$rows_ref);
Deal with a mailheader.
mailquote
$self->mailquote(line_ref=>$line_ref,
line_action_ref=>$line_action_ref,
prev_ref=>$prev_ref,
prev_action_ref=>$prev_action_ref,
next_ref=>$next_ref);
Deal with quoted mail.
subtract_modes
$newvector = subtract_modes($vector, $mask);
Subtracts modes listed in $mask from $vector.
paragraph
$self->paragraph(line_ref=>$line_ref,
line_action_ref=>$line_action_ref,
prev_ref=>$prev_ref,
prev_action_ref=>$prev_action_ref,
line_indent=>$line_indent,
prev_indent=>$prev_indent,
is_fragment=>$is_fragment,
ind=>$ind);
Detect paragraph indentation.
listprefix
($prefix, $number, $rawprefix, $term) = $self->listprefix($line);
Detect and parse a list item.
startlist
$self->startlist(prefix=>$prefix,
number=>0,
rawprefix=>$rawprefix,
term=>$term,
para_lines_ref=>$para_lines_ref,
para_action_ref=>$para_action_ref,
ind=>0,
prev_ref=>$prev_ref,
total_prefix=>$total_prefix);
Start a list.
endlist
$self->endlist(num_lists=>0,
prev_ref=>$prev_ref,
line_action_ref=>$line_action_ref);
End N lists
continuelist
$self->continuelist(para_lines_ref=>$para_lines_ref,
para_action_ref=>$para_action_ref,
ind=>0,
term=>$term);
Continue a list.
liststuff
$self->liststuff(para_lines_ref=>$para_lines_ref,
para_action_ref=>$para_action_ref,
para_line_indent_ref=>$para_line_indent_ref,
ind=>0,
prev_ref=>$prev_ref);
Process a list (higher-level method).
get_table_type
$table_type = $self->get_table_type(rows_ref=>$rows_ref,
para_len=>0);
Figure out the table type of this table, if any
is_aligned_table
if ($self->is_aligned_table(rows_ref=>$rows_ref, para_len=>0))
{
...
}
Check if the given paragraph-array is an aligned table
is_pgsql_table
if ($self->is_pgsql_table(rows_ref=>$rows_ref, para_len=>0))
{
...
}
Check if the given paragraph-array is a Postgresql table (the ascii format produced by Postgresql)
A PGSQL table can start with an optional table-caption,
then it has a row of column headings separated by |
then it has a row of ------+-----
then it has one or more rows of column values separated by |
then it has a row-count (N rows)
is_border_table
if ($self->is_border_table(rows_ref=>$rows_ref, para_len=>0))
{
...
}
Check if the given paragraph-array is a Border table.
A BORDER table can start with an optional table-caption,
then it has a row of +------+-----+
then it has a row of column headings separated by |
then it has a row of +------+-----+
then it has one or more rows of column values separated by |
then it has a row of +------+-----+
is_delim_table
if ($self->is_delim_table(rows_ref=>$rows_ref, para_len=>0))
{
...
}
Check if the given paragraph-array is a Delimited table.
A DELIM table can start with an optional table-caption, then it has at least two rows which start and end
and are punctuated by a non-alphanumeric delimiter.
| val1 | val2 |
| val3 | val4 |
tablestuff
$self->tablestuff(table_type=>0,
rows_ref=>$rows_ref,
para_len=>0);
Process a table.
make_aligned_table
$self->make_aligned_table(rows_ref=>$rows_ref,
para_len=>0);
Make an Aligned table.
make_pgsql_table
$self->make_pgsql_table(rows_ref=>$rows_ref,
para_len=>0);
Make a PGSQL table.
make_border_table
$self->make_border_table(rows_ref=>$rows_ref,
para_len=>0);
Make a BORDER table.
make_delim_table
$self->make_delim_table(rows_ref=>$rows_ref,
para_len=>0);
Make a Delimited table.
is_preformatted
if ($self->is_preformatted($line))
{
...
}
Returns true if the passed string is considered to be preformatted.
split_end_explicit_preformat
$front = $self->split_end_explicit_preformat(para_ref=>$para_ref);
Modifies the given string, and returns the front preformatted part.
endpreformat
$self->endpreformat(para_lines_ref=>$para_lines_ref,
para_action_ref=>$para_action_ref,
ind=>0,
prev_ref=>$prev_ref);
End a preformatted section.
preformat
$self->preformat(mode_ref=>$mode_ref,
line_ref=>$line_ref,
line_action_ref=>$line_action_ref,
prev_ref=>$prev_ref,
next_ref=>$next_ref,
prev_action_ref);
Detect and process a preformatted section.
make_new_anchor
$anchor = $self->make_new_anchor($heading_level);
Make a new anchor.
anchor_mail
$self->anchor_mail($line_ref);
Make an anchor for a mail section.
anchor_heading
$self->anchor_heading($heading_level, $line_ref);
Make an anchor for a heading.
heading_level
$self->heading_level($style);
Add a new heading style if this is a new heading style.
is_ul_list_line
if ($self->is_ul_list_line($line))
{
...
}
Tests if this line starts a UL list item.
is_heading
if ($self->is_heading(line_ref=>$line_ref, next_ref=>$next_ref))
{
...
}
Tests if this line is a heading. Needs to take account of the next line, because a standard heading is
defined by "underlining" the text of the heading.
heading
$self->heading(line_ref=>$line_ref,
next_ref=>$next_ref);
Make a heading. Assumes is_heading is true.
is_custom_heading
if ($self->is_custom_heading($line))
{
...
}
Check if the given line matches a custom heading.
custom_heading
$self->custom_heading(line_ref=>$line_ref);
Make a custom heading. Assumes is_custom_heading is true.
unhyphenate_para
$self->unhyphenate_para($para_ref);
Join up hyphenated words that are split across lines.
tagline
$self->tagline($tag, $line_ref);
Put the given tag around the given line.
iscaps
if ($self->iscaps($line))
{
...
}
Check if a line is all capitals.
caps
$self->caps(line_ref=>$line_ref,
line_action_ref=>$line_action_ref);
Detect and deal with an all-caps line.
do_delim
$self->do_delim(line_ref=>$line_ref,
line_action_ref=>$line_action_ref,
delim=>'*',
tag=>'STRONG');
Deal with a line which has words delimited by the given delimiter; this is used to deal with italics,
bold and underline formatting.
glob2regexp
$regexp = glob2regexp($glob);
Convert very simple globs to regexps
add_regexp_to_links_table
$self->add_regexp_to_links_table(label=>$label,
pattern=>$pattern,
url=>$url,
switches=>$switches);
Add the given regexp "link definition" to the links table.
add_literal_to_links_table
$self->add_literal_to_links_table(label=>$label,
pattern=>$pattern,
url=>$url,
switches=>$switches);
Add the given literal "link definition" to the links table.
add_glob_to_links_table
$self->add_glob_to_links_table(label=>$label,
pattern=>$pattern,
url=>$url,
switches=>$switches);
Add the given glob "link definition" to the links table.
parse_dict
$self->parse_dict($dictfile, $dict);
Parse the dictionary file. (see also load_dictionary_links, for things that were stripped)
setup_dict_checking
$self->setup_dict_checking();
Set up the dictionary checking.
in_link_context
if ($self->in_link_context($match, $before))
{
...
}
Check if we are inside a link (<a ...>); certain kinds of substitution are not allowed here.
apply_links
$self->apply_links(para_ref=>$para_ref,
para_action_ref=>$para_action_ref);
Apply links and formatting to this paragraph.
check_dictionary_links
$self->check_dictionary_links(line_ref=>$line_ref,
line_action_ref=>$line_action_ref);
Check (and alter if need be) the bits in this line matching the patterns in the link dictionary.
load_dictionary_links
$self->load_dictionary_links();
Load the dictionary links.
do_file_start
$self->do_file_start($outhandle, $para);
Extra stuff needed for the beginning: HTML headers, and prepending a file if desired.
do_init_call
$self->do_init_call();
Certain things, like reading link dictionaries, need to be done only once.
FILE FORMATS
There are two files which are used which can affect the outcome of the conversion. One is the link
dictionary, which contains patterns (of how to recognise http links and other things) and how to convert
them. The other is, naturally, the format of the input file itself.
Link Dictionary
A link dictionary file contains patterns to match, and what to convert them to. It is called a "link"
dictionary because it was intended to be something which defined what a href link was, but it can be used
for more than that. However, if you wish to define your own links, it is strongly advised to read up on
regular expressions (regexes) because this relies heavily on them.
The file consists of comments (which are lines starting with #) and blank lines, and link entries. Each
entry consists of a regular expression, a -> separator (with optional flags), and a link "result".
In the simplest case, with no flags, the regular expression defines the pattern to look for, and the
result says what part of the regular expression is the actual link, and the link which is generated has
the href as the link, and the whole matched pattern as the visible part of the link. The first character
of the regular expression is taken to be the separator for the regex, so one could either use the
traditional / separator, or something else such as | (which can be helpful with URLs which are full of /
characters).
So, for example, an ftp URL might be defined as:
|ftp:[\w/\.:+\-]+| -> $&
This takes the whole pattern as the href, and the resultant link has the same thing in the href as in the
contents of the anchor.
But sometimes the href isn't the whole pattern.
/<URL:\s*(\S+?)\s*>/ --> $1
With the above regex, a () grouping marks the first subexpression, which is represented as $1 (rather
than $& the whole expression). This entry matches a URL which was marked explicitly as a URL with the
pattern <URL:foo> (note the < is shown as the entity, not the actual character. This is because by
the time the links dictionary is checked, all such things have already been converted to their HTML
entity forms, unless, of course, the escape_HTML_chars option was turned off) This would give us a link
in the form <A HREF="foo"><URL:foo></A>
The h flag
However, if we want more control over the way the link is constructed, we can construct it ourself. If
one gives the h flag, then the "result" part of the entry is taken not to contain the href part of the
link, but the whole link.
For example, the entry:
/<URL:\s*(\S+?)\s*>/ -h-> <A HREF="$1">$1</A>
will take <URL:foo> and give us <A HREF="foo">foo</A>
However, this is a very powerful mechanism, because it can be used to construct custom tags which aren't
links at all. For example, to flag *italicised words* the following entry will surround the words with
EM tags.
/\B\*([a-z][a-z -]*[a-z])\*\B/ -hi-> <EM>$1</EM>
The i flag
This turns on ignore case in the pattern matching.
The e flag
This turns on execute in the pattern substitution. This really only makes sense if h is turned on too.
In that case, the "result" part of the entry is taken as perl code to be executed, and the result of that
code is what replaces the pattern.
The o flag
This marks the entry as a once-only link. This will convert the first instance of a matching pattern,
and ignore any others further on.
For example, the following pattern will take the first mention of HTML::TextToHTML and convert it to a
link to the module's home page.
"HTML::TextToHTML" -io-> http://www.katspace.com/tools/text_to_html/
Input File Format
For the most part, this module tries to use intuitive conventions for determining the structure of the
text input. Unordered lists are marked by bullets; ordered lists are marked by numbers or letters; in
either case, an increase in indentation marks a sub-list contained in the outer list.
Headers (apart from custom headers) are distinguished by "underlines" underneath them; headers in all-
capitals are distinguished from those in mixed case. All headers, both normal and custom headers, are
expected to start at the first line in a "paragraph".
In other words, the following is a header:
I am Head Man
-------------
But the following does not have a header:
I am not a head Man, man
I am Head Man
-------------
Tables require a more rigid convention. A table must be marked as a separate paragraph, that is, it must
be surrounded by blank lines. Tables come in different types. For a table to be parsed, its
--table_type option must be on, and the --make_tables option must be true.
ALIGN Table Type
Columns must be separated by two or more spaces (this prevents accidental incorrect recognition of a
paragraph where interword spaces happen to line up). If there are two or more rows in a paragraph and
all rows share the same set of (two or more) columns, the paragraph is assumed to be a table. For
example
-e File exists.
-z File has zero size.
-s File has nonzero size (returns size).
becomes
<table>
<tr><td>-e</td><td>File exists.</td></tr>
<tr><td>-z</td><td>File has zero size.</td></tr>
<tr><td>-s</td><td>File has nonzero size (returns size).</td></tr>
</table>
This guesses for each column whether it is intended to be left, centre or right aligned.
BORDER Table Type
This table type has nice borders around it, and will be rendered with a border, like so:
+---------+---------+
| Column1 | Column2 |
+---------+---------+
| val1 | val2 |
| val3 | val3 |
+---------+---------+
The above becomes
<table border="1">
<thead><tr><th>Column1</th><th>Column2</th></tr></thead>
<tbody>
<tr><td>val1</td><td>val2</td></tr>
<tr><td>val3</td><td>val3</td></tr>
</tbody>
</table>
It can also have an optional caption at the start.
My Caption
+---------+---------+
| Column1 | Column2 |
+---------+---------+
| val1 | val2 |
| val3 | val3 |
+---------+---------+
PGSQL Table Type
This format of table is what one gets from the output of a Postgresql query.
Column1 | Column2
---------+---------
val1 | val2
val3 | val3
(2 rows)
This can also have an optional caption at the start. This table is also rendered with a border and
table-headers like the BORDER type.
DELIM Table Type
This table type is delimited by non-alphanumeric characters, and has to have at least two rows and two
columns before it's recognised as a table.
This one is delimited by the '| character:
| val1 | val2 |
| val3 | val3 |
But one can use almost any suitable character such as : # $ % + and so on. This is clever enough to
figure out what you are using as the delimiter if you have your data set up like a table. Note that the
line has to both begin and end with the delimiter, as well as using it to separate values.
This can also have an optional caption at the start.
EXAMPLES
use HTML::TextToHTML;
Create a new object
my $conv = new HTML::TextToHTML();
my $conv = new HTML::TextToHTML(title=>"Wonderful Things",
default_link_dict=>$my_link_file,
);
Add further arguments
$conv->args(short_line_length=>60,
preformat_trigger_lines=>4,
caps_tag=>"strong",
);
Convert a file
$conv->txt2html(infile=>[$text_file],
outfile=>$html_file,
title=>"Wonderful Things",
mail=>1
);
Make a pipleline
open(IN, "ls |") or die "could not open!";
$conv->txt2html(inhandle=>[\*IN],
outfile=>'-',
);
NOTES
• If the underline used to mark a header is off by more than 1, then that part of the text will not be
picked up as a header unless you change the value of --underline_length_tolerance and/or
--underline_offset_tolerance. People tend to forget this.
REQUIRES
HTML::TextToHTML requires Perl 5.8.1 or later.
For installation, it needs:
Module::Build
The txt2html script needs:
Getopt::Long
Getopt::ArgvFile
Pod::Usage
File::Basename
For testing, it also needs:
Test::More
For debugging, it also needs:
YAML::Syck
INSTALLATION
Make sure you have the dependencies installed first! (see REQUIRES above)
Some of those modules come standard with more recent versions of perl, but I thought I'd mention them
anyway, just in case you may not have them.
If you don't know how to install these, try using the CPAN module, an easy way of auto-installing modules
from the Comprehensive Perl Archive Network, where the above modules reside. Do "perldoc perlmodinstall"
or "perldoc CPAN" for more information.
To install this module type the following:
perl Build.PL
./Build
./Build test
./Build install
Or, if you're on a platform (like DOS or Windows) that doesn't like the "./" notation, you can do this:
perl Build.PL
perl Build
perl Build test
perl Build install
In order to install somewhere other than the default, such as in a directory under your home directory,
like "/home/fred/perl" go
perl Build.PL --install_base /home/fred/perl
as the first step instead.
This will install the files underneath /home/fred/perl.
You will then need to make sure that you alter the PERL5LIB variable to find the modules, and the PATH
variable to find the script.
Therefore you will need to change: your path, to include /home/fred/perl/script (where the script will
be)
PATH=/home/fred/perl/script:${PATH}
the PERL5LIB variable to add /home/fred/perl/lib
PERL5LIB=/home/fred/perl/lib:${PERL5LIB}
Note that the system links dictionary will be installed as "/home/fred/perl/share/txt2html/txt2html.dict"
If you want to install in a temporary install directory (such as if you are building a package) then
instead of going
perl Build install
go
perl Build install destdir=/my/temp/dir
and it will be installed there, with a directory structure under /my/temp/dir the same as it would be if
it were installed plain. Note that this is NOT the same as setting --install_base, because certain
things are done at build-time which use the install_base info.
See "perldoc perlrun" for more information on PERL5LIB, and see "perldoc Module::Build" for more
information on installation options.
BUGS
Please, send to https://github.com/resurrecting-open-source-projects/txt2html/issues
SEE ALSO
perl txt2html.
AUTHOR
Kathryn Andersen (RUBYKAT)
perlkat AT katspace dot com
http//www.katspace.com/
based on txt2html by Seth Golub
COPYRIGHT AND LICENCE
Original txt2html script copyright (c) 1994-2000 Seth Golub <seth AT aigeek.com>
Copyright (c) 2002-2005 by Kathryn Andersen <perlkat AT katspace dot com>
Copyright (c) 2018-2019 Joao Eriberto Mota Filho <eriberto@eriberto.pro.br> Copyright (c) 2019 Bruce
Momjian <bruce@momjian.us>
This program is free software; you can redistribute it and/or modify it under the same terms as Perl
itself.
perl v5.36.0 2022-11-23 HTML::TextToHTML(3pm)