Null object: Difference between revisions
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m (→{{header|REXX}}: expanded the title of the REXX program. -- ~~~~) |
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<br>A variable with a NULL value has a length of 0 (zero). |
<br>A variable with a NULL value has a length of 0 (zero). |
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<br><br>The DROP statement can be used to "un-define" a REXX variable. |
<br><br>The DROP statement can be used to "un-define" a REXX variable. |
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<lang rexx>/*REXX |
<lang rexx>/*REXX program demonstrates null strings, and also undefined values. */ |
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if symbol('ABC')=="VAR" then say 'variable ABC is defined, value='abc"<<<" |
if symbol('ABC')=="VAR" then say 'variable ABC is defined, value='abc"<<<" |
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