doc_src/begin.txt


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\section begin begin - start a new block of code

\subsection begin-synopsis Synopsis
 <tt>begin; [COMMANDS...;] end</tt>

\subsection begin-description Description

\c begin is used to create a new block of code.

The block
is unconditionally executed. <code>begin; ...; end</tt> is equivalent
to <tt>if true; ...; end</tt>.

\c begin is used to group a number of commands into a block.
This 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 \c and.

\c begin does not change the current exit status.

\subsection begin-example 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.

<pre>
begin
	set -l PIRATE Yarrr
	...
end
# This will not output anything, since the PIRATE variable went out
# of scope at the end of the block
echo $PIRATE
</pre>

In the following code, all output is redirected to the file out.html.

<pre>
begin
	echo $xml_header
	echo $html_header
	if test -e $file
		...
	end
	...

end &gt; out.html
</pre>