Path: utzoo!attcan!uunet!clyde.concordia.ca!mcgill-vision!snorkelwacker!apple!voder!procase!roger
From: roger@procase.UUCP (Roger H. Scott)
Newsgroups: comp.lang.c++
Subject: Re: constructor called within constructor???
Message-ID: <174@logo.procase.UUCP>
Date: 11 Jul 90 01:49:10 GMT
References: <965@unet.UUCP> <11017@alice.UUCP>
Reply-To: roger@procase.UUCP (Roger H. Scott)
Organization: proCASE Corporation, Santa Clara, CA
Lines: 44

Andrew Koenig's "helper" functions [build()] don't solve the problem of
factoring out common *initialization*.  For example,

    class Base {
    public:
	Base(int, double, char *, char *);
	...
    };

    class String {
    public:
	String(char *);
	...
    };

    class Derived : public Base {
    public:
	Derived() : Base(2, 4.6, "foo", "bar"), Mem1("aack"), Mem2("pfft"),
	    myI(0), myJ(0) {
	}
	Derived(int i) : Base(2, 4.6, "foo", "bar"), Mem1("aack"), Mem2("pfft"),
	    myI(i), myJ(0) {
	}
	Derived(int i, int j):Base(2,4.6,"foo","bar"),Mem1("aack"),Mem2("pfft"),
	    myI(i), myJ(j) {
	}

    private:
	String Mem1, Mem2;
	int myI, myJ;
    };

A long time ago I asked the AT&T folks to define

    class Foo {
    public:
	Foo();
	Foo(int i) : Foo(), myI(i) {}
    };

to mean "to construct a Foo object from an integer, construct a Foo object
using the default Foo constructor and then execute the remainder of the
Foo(int) constructor body".  This is by analogy with "Derived() : Base() {}".
Needless to say, my idea was not adopted.