[Array->ForEach] invokes a tag, type, or compound expression on each element in the array. The tag requires a single parameter which is a tag reference, data type instance, or compound expression. The parameter is invoked on each element of the array in turn (i.e. the tag is called with each element of the array as a parameter in turn). The parameter must return True for the tag to continue. If the parameter returns False then the operation is halted.

The parameter can modify the array by modifying the array element which is passed into it by reference.

[Var: 'array' = (Array: 1, 2, 3, 4)]
[Define_Tag: 'Ex_Square', -Required='value']
  [#value *= #value]
  [Return: True]
[/Define_Tag]
[$array->(ForEach: \Ex_Square)]