fish-shell/sphinx_doc_src/cmds/for.rst

for - perform a set of commands multiple times.
===============================================

Synopsis
--------

for VARNAME in [VALUES...]; COMMANDS...; end


Description
-----------

``for`` is a loop construct. It will perform the commands specified by ``COMMANDS`` multiple times. On each iteration, the local variable specified by ``VARNAME`` is assigned a new value from ``VALUES``. If ``VALUES`` is empty, ``COMMANDS`` will not be executed at all. The ``VARNAME`` is visible when the loop terminates and will contain the last value assigned to it. If ``VARNAME`` does not already exist it will be set in the local scope. For our purposes if the ``for`` block is inside a function there must be a local variable with the same name. If the ``for`` block is not nested inside a function then global and universal variables of the same name will be used if they exist.

Example
-------



::

    for i in foo bar baz; echo $i; end
    
    # would output:
    foo
    bar
    baz


Notes
-----

The ``VARNAME`` was local to the for block in releases prior to 3.0.0. This means that if you did something like this:



::

    for var in a b c
        if break_from_loop
            break
        end
    end
    echo $var


The last value assigned to ``var`` when the loop terminated would not be available outside the loop. What ``echo $var`` would write depended on what it was set to before the loop was run. Likely nothing.