Call an object method: Difference between revisions

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(Add Factor example)
(→‎{{header|Factor}}: change a class to a regular tuple; makes for a better example)
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In Factor, there is no distinction between instance and static methods. Methods are contained in generic words and specialize on a class. Generic words define a <i>method combination</i> so methods know which object(s) to dispatch on. (But most methods dispatch on the object at the top of the data stack.) Under this object model, calling a method is no different than calling any other word.
In Factor, there is no distinction between instance and static methods. Methods are contained in generic words and specialize on a class. Generic words define a <i>method combination</i> so methods know which object(s) to dispatch on. (But most methods dispatch on the object at the top of the data stack.) Under this object model, calling a method is no different than calling any other word.


<lang factor>! Define some classes.
<lang factor>USING: accessors io kernel literals math sequences ;
IN: rosetta-code.call-a-method

! Define some classes.
SINGLETON: dog
SINGLETON: dog
TUPLE: cat sassiness ;
SINGLETON: cat

! Define a constructor for cat.
C: <cat> cat


! Define a generic word that dispatches on the object at the top
! Define a generic word that dispatches on the object at the top
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! Define methods in speak which specialize on various classes.
! Define methods in speak which specialize on various classes.
M: dog speak drop "Woof!" print ;
M: dog speak drop "Woof!" print ;
M: cat speak drop "Meow!" print ;
M: cat speak sassiness>> 0.5 > "Hiss!" "Meow!" ? print ;
M: object speak drop "I don't know how to speak!" print ;
M: object speak drop "I don't know how to speak!" print ;


! Place three objects of different classes on the data stack.
! Place some objects of various classes in a sequence.
dog cat 10
${ dog 0.75 <cat> 0.1 <cat> 10 }
! Call speak, a method, just like any other word.
! Call speak, a method, just like any other word.
[ speak ] tri@</lang>
[ speak ] each </lang>
{{out}}
{{out}}
<pre>
<pre>
Woof!
Woof!
Hiss!
Meow!
Meow!
I don't know how to speak!
I don't know how to speak!
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