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sphinx_doc_src/cmds/while.rst

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+\section while while - perform a command multiple times
+
+\subsection while-synopsis Synopsis
+\fish{synopsis}
+while CONDITION; COMMANDS...; end
+\endfish
+
+\subsection while-description Description
+
+`while` repeatedly executes `CONDITION`, and if the exit status is 0, then executes `COMMANDS`.
+
+If the exit status of `CONDITION` is non-zero on the first iteration, `COMMANDS` will not be
+executed at all, and the exit status of the loop set to the exit status of `CONDITION`.
+
+The exit status of the loop is 0 otherwise.
+
+You can use <a href="#and">`and`</a> or <a href="#or">`or`</a> for complex conditions. Even more complex control can be achieved with `while true` containing a <a href="#break">break</a>.
+
+\subsection while-example Example
+
+\fish
+while test -f foo.txt; or test -f bar.txt ; echo file exists; sleep 10; end
+# outputs 'file exists' at 10 second intervals as long as the file foo.txt or bar.txt exists.
+\endfish