Revision as of 18:28, 22 August 2015 (view source) rosettacode>G.Brougnard (Added EchoLisp) ← Older edit		Revision as of 20:25, 22 August 2015 (view source) Walterpachl (talk \| contribs) m (→‎{{header\|ooRexx}}: typo) Newer edit →
Line 852: =={{header\|ooRexx}}== ooRexx has a special singleton object ~~call~~called .nil that is used to indicate the absence of values in some situations (such as the default values returned from collection objects). <lang ooRexx> if a[i] == .nil then say "Item" i "is missing" Line 863: if \var("var") then say "Variable" var "is not assigned"</lang> Output: <pre>Item 3 of array A is missing▼ ~~<pre>~~ ▲Item 3 of array A is missing Variable INPUT is not assigned Variable VAR is not assigned</pre> ~~</pre>~~ =={{header\|Oz}}==

Null object: Difference between revisions

Null object (view source)