fish-shell/doc_src/begin.txt
2014-09-03 14:43:26 +01:00

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\section begin begin - start a new block of code
\subsection begin-synopsis Synopsis
\fish{synopsis}
begin; [COMMANDS...;] end
\endfish
\subsection begin-description Description
`begin` is used to create a new block of code.
The block is unconditionally executed. `begin; ...; end` is equivalent to `if true; ...; end`.
`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 `and`.
`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.
\fish
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
\endfish
In the following code, all output is redirected to the file out.html.
\fish
begin
echo $xml_header
echo $html_header
if test -e $file
...
end
...
end > out.html
\endfish