doc_src/cmds/eval.rst

.. _cmd-eval:

eval - evaluate the specified commands
======================================

Synopsis
--------

**eval** [*COMMANDS*...]

Description
-----------
**eval** evaluates the specified parameters as a command.
If more than one parameter is specified, all parameters will be joined using a space character as a separator.

If the command does not need access to stdin, consider using :ref:`source <cmd-source>` instead.

If no piping or other compound shell constructs are required, variable-expansion-as-command, as in  ``set cmd ls -la; $cmd``, is also an option.

Example
-------

The following code will call the ls command and truncate each filename to the first 12 characters.

::

    set cmd ls \| cut -c 1-12
    eval $cmd
docs: Add labels to all commands This allows us to use :ref: references, which don't require hardcoding it as html [ci skip] 2019-03-31 11:05:09 +02:00			`.. _cmd-eval:`

Switch command docs from \section to reStructuredText 2018-12-16 17:39:33 -08:00			`eval - evaluate the specified commands`
Fix command section separator line lengths 2019-01-02 20:10:47 -08:00			`======================================`
Switch command docs from \section to reStructuredText 2018-12-16 17:39:33 -08:00
Migrate the 'synopsis' sections to .rst format 2018-12-17 17:58:24 -08:00			`Synopsis`
			`--------`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 13:08:41 -08:00
Commit doc_src progress. This is continuing the work I've been doing to remove the :: formatting for the synopsis sections of our manual pages. 2021-12-17 13:58:38 -08:00			`eval [COMMANDS...]`
Migrate the 'synopsis' sections to .rst format 2018-12-17 17:58:24 -08:00
Convert \\subsection sections into rst format 2018-12-18 18:44:30 -08:00			`Description`
Fix command section separator line lengths 2019-01-02 20:10:47 -08:00			`-----------`
Commit doc_src progress. This is continuing the work I've been doing to remove the :: formatting for the synopsis sections of our manual pages. 2021-12-17 13:58:38 -08:00			`eval evaluates the specified parameters as a command.`
			`If more than one parameter is specified, all parameters will be joined using a space character as a separator.`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 13:08:41 -08:00
Commit doc_src progress. This is continuing the work I've been doing to remove the :: formatting for the synopsis sections of our manual pages. 2021-12-17 13:58:38 -08:00			If the command does not need access to stdin, consider using :ref:`source <cmd-source>` instead.
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 13:08:41 -08:00
"eval" example to use $cmd as an array Signed-off-by: Osamu Aoki <osamu@debian.org> 2019-11-19 00:02:21 +09:00			If no piping or other compound shell constructs are required, variable-expansion-as-command, as in ``set cmd ls -la; $cmd``, is also an option.
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 13:08:41 -08:00
Variables as commands are in fact supported, eval docs should not claim otherwise. (#5819) Provide an example that somewhat justifies eval's existence in light of this change. Also correct similar misinformation found in a comment. 2019-04-26 23:00:13 +09:30			`Example`
			`-------`
Switch \fish sections to rst format 2018-12-18 19:14:04 -08:00
Variables as commands are in fact supported, eval docs should not claim otherwise. (#5819) Provide an example that somewhat justifies eval's existence in light of this change. Also correct similar misinformation found in a comment. 2019-04-26 23:00:13 +09:30			`The following code will call the ls command and truncate each filename to the first 12 characters.`
Switch \fish sections to rst format 2018-12-18 19:14:04 -08:00
			`::`

Variables as commands are in fact supported, eval docs should not claim otherwise. (#5819) Provide an example that somewhat justifies eval's existence in light of this change. Also correct similar misinformation found in a comment. 2019-04-26 23:00:13 +09:30			`set cmd ls \\| cut -c 1-12`
Switch \fish sections to rst format 2018-12-18 19:14:04 -08:00			`eval $cmd`