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+# $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>

EPIC