The following commands can be used to inspect the contents of any variable or value:
TypeOf value v1.1
Returns a string indicating the underlying type of the value. If the value is an object, this will return the name of the object, eg: ‘Document’. Otherwise returns one of the following:
Returns |
For Value Type |
'Undefined' |
Only the @undefined value. |
'Integer' |
Any integer value, or the @true or @false values. |
'Float' |
Any float (decimal) value. |
'String' |
Any string that does not define attributes. |
'Text' |
Any string that defines attributes. |
'Array' |
Any array value. |
'Hash' |
Any hash value. |
'Data' |
The value is an uninterpreted block of bytes. |
Returns @true if the value is defined, otherwise @false. All values are defined (even @false) except the special @undefined value, which is returned by some commands to indicate a failure or other special circumstances.
As of v3.0.2 you may also test an undeclared variable:
If ! Defined($goal)
Prompt "We haven't yet defined our goal."
End
$goal = "give fruit"
If Defined($goal)
Prompt "Our goal is to $goal."
End
In prior versions the above code example would show a user-visible error, alerting that the variable was unknown.
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