This shows you the differences between two versions of the page.
— |
shift_function [2007/08/06 21:25] (current) |
||
---|---|---|---|
Line 1: | Line 1: | ||
+ | # $EPIC: shift_function.txt,v 1.5 2007/08/06 21:25:50 jnelson Exp $ | ||
+ | ======Synopsis:====== | ||
+ | $__shift__(<variable name>) | ||
+ | |||
+ | ======Description:====== | ||
+ | The function takes only one argument, a variable name. The variable is | ||
+ | changed by removing its first [[what is a word|word]]. The function then | ||
+ | returns that first word. | ||
+ | |||
+ | ======Practical:====== | ||
+ | This function can destructively remove the first word from an [[lval]]ue | ||
+ | ([[ASSIGN]] variable), or non-destructively remove the first word from | ||
+ | an rvalue (string of text). This is an essential operation when you are | ||
+ | creating LIFOs, FIFOs, or other types of queues. | ||
+ | |||
+ | ======Returns:====== | ||
+ | The first word, which is "shifted" off of the variable, or the word list, | ||
+ | whichever applies. If a variable name is provided, the variable IS CHANGED. | ||
+ | |||
+ | ======Examples:====== | ||
+ | <file> | ||
+ | assign foo blah booya | ||
+ | $shift(foo) removes "blah" from $foo and returns "blah". | ||
+ | </file> | ||