**(for: // [[harlowe:Lambda|lambda]], ...Any//) -> //[[harlowe:Changer|changer]]//**

Also known as: [[harlowe:loop|(loop:)]]

A [[harlowe:command|command]] that repeats the attached hook, setting a temporary variable to a different value on each repeat.

=== Example usage: ===

  * ''%%(for: each _item, ...$arr) [You have the _item.]%%'' prints "You have the " and the item, for each item in $arr.
  * ''%%(for: _ingredient where it contains "petal", ...$reagents) [Cook the _ingredient?]%%'' prints "Cook the " and the [[harlowe:string|string]], for each string in $reagents which contains "petal".

=== Rationale: ===

Suppose you're using [[harlowe:array|arrays]] to store strings representing inventory items, or character [[harlowe:datamap|datamaps]],
or other kinds of sequential game information - or even just built-in arrays like [[harlowe:history|(history:)]] - and you
want to print out a sentence or paragraph for each item. The (for:) macro can be used to print something "for each"
item in an array easily - simply write a hook using a temp variable where each item should be printed or used,
then give (for:) an "each" [[harlowe:lambda|lambda]] that uses the same temp variable.

=== Details: ===

Don't make the mistake of believing you can alter an array by trying to [[harlowe:set|(set:)]] the temp variable in each loop - such
as ''%%(for: each _a, ...$arr)[(set: _a to it + 1)]%%''. This will NOT change $arr - only the temp variable will change (and
only until the next loop, where another $arr value will be put into it). If you want to alter an array item-by-item, use
the [[harlowe:altered|(altered:)]] macro.

The temp variable inside the hook will shadow any other identically-named temp variables outside of it: if you
''%%(set: _a to 1)%%'', then ''%%(for: each _a, 2,3)[ (print: _a) ]%%'', the inner hook will print "2" and "3", and you won't be
able to print or set the "outer" _a.

You may want to simply print several copies of a hook a certain [[harlowe:number|number]] of times, without any particular
array data being looped over. You can use the [[harlowe:range|(range:)]] macro with it instead: ''%%(for: each _i in ...(range:1,10))%%'', and
not use the temp variable inside the hook at all.

As it is a [[harlowe:changer|changer]] macro, (for:)'s value is a changer command which can be stored in a variable - this command stores all
of the values originally given to it, and won't reflect any changes to the values, or their container arrays, since then.

=== Alternatives: ===

You may be tempted to use (for:) not to print anything at all, but to find values inside arrays using [[harlowe:if|(if:)]], or
form a "total" using [[harlowe:set|(set:)]]. The lambda macros [[harlowe:find|(find:)]] and [[harlowe:folded|(folded:)]], while slightly less straightforward,
are recommended to be used instead.

=== See also: ===

[[harlowe:find|(find:)]], [[harlowe:folded|(folded:)]], [[harlowe:if|(if:)]]