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HELP FOREACH SH JLC, July 1982 foreach <pattern> do <actions> endforeach; foreach <pattern> in <list> do <actions> endforeach; FOREACH is used for iteration over a database consisting of a list of lists. The <pattern> is matched (see HELP *MATCHES) against each element of the database, which defaults to the value of the variable *DATABASE when the IN <LIST> clause is omitted. After each successful match, the item that matched the pattern is bound to the variable IT and the <actions> are performed. Usually, the match will have side-effected the value of some variables in the pattern. E.g. vars x list; [[a is big] [b is small] [c is big] [d is small]] -> list; foreach [?x is big] in list do it=> [therefore ^x is heavy] => endforeach; ** [a is big] ** [therefore a is heavy] ** [c is big] ** [therefore c is heavy] See also HELP *MATCHES - summary of the matcher *FOREVERY - like FOREACH, but matches a list of patterns against a database *DATABASE - describes the use of the POP-11 DATABASE *LOOPS - for other types of iteration *FOR - iteration over lists and numbers