This is an automatically generated page and cannot be edited directly. Text in Composite pages, (URLs starting with 'routine' or 'syntax') can be edited by clicking on the link labeled 'in context', and editing the text there.

Exit this popup by pressing <Escape>, or clicking on X or on the background.

defined
Combined from primary sources listed below.

In Failure§

See primary documentation in context for method defined 

multi method defined(Failure:D: --> Bool:D)

Returns False (failures are officially undefined), and marks the failure as handled.

sub f() { fail };
my $v = f;
say $v.handled; # OUTPUT: «False␤» 
say $v.defined; # OUTPUT: «False␤» 
say $v.handled; # OUTPUT: «True␤»

In Mu§

See primary documentation in context for method defined 

multi method defined(   --> Bool:D)

Returns False on a type object, and True otherwise.

say Int.defined;                # OUTPUT: «False␤» 
say 42.defined;                 # OUTPUT: «True␤»

A few types (like Failure) override defined to return False even for instances:

sub fails() { fail 'oh noe' };
say fails().defined;            # OUTPUT: «False␤»

In Mu§

See primary documentation in context for routine defined 

multi defined(Mu --> Bool:D)

invokes the .defined method on the object and returns its result.

In Junction§

See primary documentation in context for method defined 

multi method defined(Junction:D:)

Checks for definedness instead of Boolean values.

say ( 3 | Str).defined ;   # OUTPUT: «True␤» 
say (one 3, Str).defined;  # OUTPUT: «True␤» 
say (none 3, Str).defined; # OUTPUT: «False␤»

Failures are also considered non-defined:

my $foo=Failure.new;
say (one 3, $foo).defined; # OUTPUT: «True␤»

Since 6.d, this method will autothread.