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/Fish 3.1

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.

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Licensed under the GNU General Public License, version 2.
https://fishshell.com/docs/3.1/cmds/for.html