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The range expression extracts a specified subsequence from a list or string:


The three expressions are evaluated in order. Expression-1 must return a list or string (the sequence) and the other two expressions must return integers (the low and high indices, respectively); otherwise, E_TYPE is raised. The $ expression can be used in either or both of expression-2 and expression-3 just as before, meaning the length of the value of expression-1.

If the low index is greater than the high index, then the empty string or list is returned, depending on whether the sequence is a string or a list. Otherwise, both indices must be between 1 and the length of the sequence; E_RANGE is raised if they are not. A new list or string is returned that contains just the elements of the sequence with indices between the low and high bounds.

"foobar"[2..$]                       =>  "oobar"
"foobar"[3..3]                       =>  "o"
"foobar"[17..12]                     =>  ""
{"one", "two", "three"}[$ - 1..$]    =>  {"two", "three"}
{"one", "two", "three"}[3..3]        =>  {"three"}
{"one", "two", "three"}[17..12]      =>  {}

This document was generated by Roger Crew on June, 2 2004 using texi2html