NAME

       jx_repl - interactive command line tool to explore the JX expression language.

SYNOPSIS

       jx_repl

DESCRIPTION

       jx_repl  is  an  interactive  tool  to  explore  the  JX  expression language.  jx_repl will read in a JX
       expression, evaluate it, print the result, then save both the  query  and  the  result  to  the  context.
       Results  of  previous expressions can be referenced via the out_%d` symbol, and their corresponding query
       via the `in_%d` symbol.  The program will exit on EOF or when the user enters 'quit' or 'exit.

       jx_repl also reserves certain symbols in the context to act as commands when entered:

       •   help display a help message which lists details on reserved commands.

       •   functions display a list of functions supported by JX.

       •   values display a list of values supported by JX.

       •   operators display a list of operators supported by JX.

       •   catalog fetch the catalog data.

       •   exit exit the program.

       •   quit same as 'exit'.

EXIT STATUS

       Will always return 0

EXAMPLES

       Simply run jx_repl with no parameters:

               % jx_repl
               Welcome to the JX Language Explorer.

               Type 'help' for help

               in_0 :

       Enter any valid JX expression:

               % jx_repl
               in_0  : [ "file" + x + ".txt" for x in range(3) ]
               out_0 :
               [
                 "file0.txt",
                 "file1.txt",
                 "file2.txt"
               ]

       Fetch the catalog data:

               % jx_repl
               in_1  : catalog
               out_1 :
               [
                 {
                   "name":NAME,
                   "lastheardfrom":1620308581,
                   "address":ADDRESS,
                   ...
                   "type":"wq_factory"
                 },

                 ...
               ]

       Perform operations on previous output

               % jx_repl
               in_2  : select(out_1, type=="wq_master")
               out_2 :
               [

                 {
                   "name":NAME,
                   "lastheardfrom":1620308755,
                   "address":ADDRESS,
                   "tasks_total_disk":0,
                   "tasks_total_memory":0,
                   ...
                   "type": wq_master
                 }
                 ...
               ]

       Do more operations on previous output

               % jx_repl
               in_3  : join(project(out_2, name), ", ")
               out_3 : NAME_1, NAME_2, NAME_3, ..., NAME_N

       Now, fetch the query used to attain that output

               % jx_repl
               in_4  : in_4
               out_4 : join(project(select(fetch("http://catalog.cse.nd.edu:9097/query.json"),type=="wq_master"),name),", ")

       Call one of reserved commands

               % jx_repl
               in_5  : help

                 help          display this message
                 functions     display a list of functions supported by the JX language
                 values        display a list of values supported by the JX language
                 operators     display a list of operators supported by the JX language
                 in_#          the #'th input query
                 out_#         result of in_#
                 catalog       alias to fetch catalog data
                 quit|exit     exit program

COPYRIGHT

       The Cooperative Computing Tools are Copyright (C) 2022 The University of Notre Dame.   This  software  is
       distributed under the GNU General Public License.  See the file COPYING for details.

CCTools 7.14.5 FINAL                                                                                  jx_repl(1)