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sphinx_doc_src/cmds/begin.rst

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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.
+
+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.
+
+
+\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