fish-shell/sphinx_doc_src/cmds/begin.rst
David Adam 02d82dcf85 docs: update all command synopsis formatting
Adds synopses for those commands missing them.

Moves all synopsis sections to code blocks. This improves the appearance, although highlighting as
fish code may not be the ideal appearance.
2019-09-17 17:59:04 +08:00

61 lines
1.3 KiB
ReStructuredText

.. _cmd-begin:
begin - start a new block of code
=================================
Synopsis
--------
::
begin; [COMMANDS...;] end
Description
-----------
``begin`` is used to create a new block of code.
A block allows the introduction of a new variable scope, redirection of the input or output of a set of commands as a group, or to specify precedence when using the conditional commands like ``and``.
The block is unconditionally executed. ``begin; ...; end`` is equivalent to ``if true; ...; end``.
``begin`` does not change the current exit status itself. After the block has completed, ``$status`` will be set to the status returned by the most recent command.
Example
-------
The following code sets a number of variables inside of a block scope. Since the variables are set inside the block and have local scope, they will be automatically deleted when the block ends.
::
begin
set -l PIRATE Yarrr
...
end
echo $PIRATE
# This will not output anything, since the PIRATE variable
# went out of scope at the end of the block
In the following code, all output is redirected to the file out.html.
::
begin
echo $xml_header
echo $html_header
if test -e $file
...
end
...
end > out.html