@node Foreach, Format, Fft, Commands

@iftex
@syntax Foreach.
@end iftex
@example
Syntax: FOREACH variable ( list ) @{ commands @}
        FOREACH variable @{ list @} @{ commands @}
        FOREACH variable WORD @{ commands @}
@end example
@pindex Foreach

   In the first two forms, the value of @code{variable} is set to each
element of list in turn,
and then the commands are executed. An example would be
@example FOREACH
var ( alpha 2 gamma ) @{ WRITE STANDARD $var @}
@end example
@noindent
which would write @code{alpha}, @code{2}, and then @code{gamma} to the
terminal (@pxref{Loops and If}).

The form with @{@} can be useful if you want the list exactly as you type it,
for example
@example
	FOREACH f @{ 0.1 $date @} @{ echo $f @}
@end example

@findex foreach, element in a vector
The form FOREACH @code{variable} WORD ... is used to iterate over a vector,
either arithmetic or string. For example,
@example
        SET str=@{Sorbus Aucuparia David Monger@}
	FOREACH f str @{ echo $f @}
@end example

It is often useful to define the FOREACH variable to be LOCAL (@pxref{Define}),
e.g. DEFINE @code{f} LOCAL in the last example.