Rexx Programming/How to Rexx/string comparison
String comparisons are made based upon lexical string order
String operators make comparisons based upon the lexical string order. Strings listed first in lexical order have a lower comparative value than strings listed later.
The following example shows a string comparison being made using the comparative operators:
animal = 'dog' if animal > 'cat' then say animal "is lexically higher than cat"
The following comparative operators are supported:
= Equal To \= Not Equal To < Less Than > Greater Than <= Less Than or Equal To >= Greater Than or Equal To \< Not Less Than \> Not Greater Than <> Not Equal To >< Not Equal To
Conventional string comparative operators ignore leading and trailing whitespace
The conventional string comparison operators ignore leading and trailing whitespace when the comparison is made:
' ' = /* 1 true, string comparison (stripped whitespace matches null value) */ 'ABC' = ' ABC ' /* 1 true, string comparison (leading and trailing whitespace ignored) */
The strict comparative operators do not ignore leading and trailing whitespace, which must also match when a strict comparison is made:
' ' == /* 0 false, strict comparison (the spaces will not match the null value) */ 'ABC' == ' ABC ' /* 0 false, strict comparison (leading and trailing whitespace causes mismatch) *# /