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From: gnelson (Greg Nelson)
Newsgroups: comp.lang.modula3
Subject: Re: Instance initialization in Modula-3?
Message-ID: <9101242209.AA14639@jumbo.pa.dec.com>
Date: 24 Jan 91 22:08:55 GMT
Lines: 16
In-Reply-To: Message of 23 Jan 91 22:11:59
    from janssen@parc.xerox.com (Bill Janssen)
    <JANSSEN.91Jan23221159@holmes.parc.xerox.com>
To: janssen@parc.xerox.com (Bill Janssen)
Cc: m3
X-Folder-Carbon: sent


The convention used in Trestle (the Modula-3 window toolkit) is that
each object type has an "init" method that returns the object after
initializing it.  So you can type

    VAR v := NEW(T).init(args)

to allocate and initialize an object of type T. If T has a supertype
S, and S uses the same convention, then T.init typically contains the
call EVAL(S.init(self)), to initialize the supertype.

This style won't work with SRC Modula-3 1.6, which doesn't let you
NEW an opaque type; but it will work soon.  There is more discussion
about this issue in the "twelve changes to Modula-3" message.

Greg