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Smalltalk lazy initialization as method call?

Having a small problem here with a variable not initializing. Are these equivalent?

comments
        ^ comments ifNil: [ comments := OrderedCollection new ]

--

comments
        ^ comments ifNil: [ self initializeComments ]

initializeComments
    comments := OrderedCollection new
Solution

  • One has to return the comments variable in the initializeComments method, otherwise the comments getter method will return self for the second variant in case of an uninitialized variable.

    I don't want to return anything in initializeComments so I used:

    comments
    ^ comments ifNil: [ self initializeComments. comments ]

    Or:

    comments
    comments ifNil: [ self initializeComments ]. 
    ^ comments

    
Thanks Mike!

    PS. For a more detailed explanation see @LeandroCaniglia answer below.