Undefined values: Difference between revisions
Content added Content deleted
m (→{{header|Prolog}}: typo) |
|||
| Line 1,124: | Line 1,124: | ||
=={{header|Prolog}}== |
=={{header|Prolog}}== |
||
Prolog has two predicates to know if a variable is |
Prolog has two predicates to know if a variable is instantiated or not: '''var/1''' and '''nonvar/1''' <br> |
||
<pre>?- var(Y). |
<pre>?- var(Y). |
||
true. |
true. |
||