.TH "jx_repl" 1 "" "CCTools 8.0.0 DEVELOPMENT" "Cooperative Computing Tools"

.SH NAME
.LP
\fBjx_repl\fP - interactive command line tool to explore the JX language.

.SH SYNOPSIS
.LP
\FC\fBjx_repl\fP\FT

.SH DESCRIPTION
.LP

\fBjx_repl\fP is an interactive tool to explore the JX language.  \fBjx_repl\fP 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.
.PP
\fBjx_repl\fP also reserves certain symbols in the context to act as commands when entered:

.IP \(bu 4
\fBhelp\fP display a help message which lists details on reserved commands.
.IP \(bu 4
\fBfunctions\fP display a list of functions supported by the JX language.
.IP \(bu 4
\fBvalues\fP display a list of values supported by the JX language.
.IP \(bu 4
\fBoperators\fP display a list of operators supported by the JX language.
.IP \(bu 4
\fBcatalog\fP fetch the catalog data.
.IP \(bu 4
\fBexit\fP exit the program.
.IP \(bu 4
\fBquit\fP same as 'exit'.


.SH EXIT STATUS
.LP
Will always return 0

.SH EXAMPLES
.LP

Simply run \fBjx_repl\fP with no parameters:

.fam C
.nf
.nh
.IP "" 8
% jx_repl
Welcome to the JX Language Explorer.

Type 'help' for help

in_0  >>>
.fi
.hy
.fam
.P

Enter any valid JX expression:

.fam C
.nf
.nh
.IP "" 8
% jx_repl
...
in_0  >>> [ "file" + x + ".txt" for x in range(3) ]
out_0 <<<
[
  "file0.txt",
  "file1.txt",
  "file2.txt"
]
.fi
.hy
.fam
.P

Fetch the catalog data:

.fam C
.nf
.nh
.IP "" 8
% jx_repl
...
in_1  >>> catalog
out_1 <<<
[
  {
    "name":NAME,
    "lastheardfrom":1620308581,
    "address":ADDRESS,
    ...
    "type":"wq_factory"
  },

  ...
]
.fi
.hy
.fam
.P

Perform operations on previous output

.fam C
.nf
.nh
.IP "" 8
% jx_repl
...
in_2  >>> select(type=="wq_master", out_1)
out_2 <<<
[

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

Do more operations on previous output

.fam C
.nf
.nh
.IP "" 8
% jx_repl
...
in_4  >>> join(project(name, out_2), ", ")
out_4 <<< NAME_1, NAME_2, NAME_3, ..., NAME_N
.fi
.hy
.fam
.P

Now, fetch the query used to attain that output

.fam C
.nf
.nh
.IP "" 8
% jx_repl
...
in_5  >>> in_4
out_5 <<< join(project(name,select(type=="wq_master",fetch("http://catalog.cse.nd.edu:9097/query.json"))),", ")
.fi
.hy
.fam
.P

Call one of reserved commands

.fam C
.nf
.nh
.IP "" 8
% jx_repl
...
in_7  >>> 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

.fi
.hy
.fam
.P


.SH COPYRIGHT
.LP

The Cooperative Computing Tools are Copyright (C) 2005-2019 The University of Notre Dame.  This software is distributed under the GNU General Public License.  See the file COPYING for details.