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47 lines
1.3 KiB
ReStructuredText
47 lines
1.3 KiB
ReStructuredText
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\section begin begin - start a new block of code
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\subsection begin-synopsis Synopsis
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\fish{synopsis}
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begin; [COMMANDS...;] end
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\endfish
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\subsection begin-description Description
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`begin` is used to create a new block of code.
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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`.
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The block is unconditionally executed. `begin; ...; end` is equivalent to `if true; ...; end`.
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`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.
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\subsection begin-example Example
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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.
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\fish
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begin
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set -l PIRATE Yarrr
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...
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end
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echo $PIRATE
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# This will not output anything, since the PIRATE variable
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# went out of scope at the end of the block
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\endfish
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In the following code, all output is redirected to the file out.html.
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\fish
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begin
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echo $xml_header
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echo $html_header
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if test -e $file
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...
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end
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...
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end > out.html
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\endfish
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