anything like C++ references?

[Duncan Booth]

owski at hotmail.com (Adam Ruth) wrote in 
news:f0f51c80.0307150921.7b6667e2 at posting.google.com:

> 2) C++ makes a strong distinction between the initialization operator,
>=, and the assignment operator, =.  Both const and reference variables
> use them differently.  To me, that's a really big violation of proper
> 'computer science', because conceptually they're the *same* thing. 
> But because of context, C++ makes a distinction.  Python has no such
> distinction, initialization and assigment are always the same.
> 
> (This is true of all static languages with the concept of a constant,
> and I don't really disagree with it as a valuable idiom, but it is
> inconsistent internally, where Python is consistent.  Do any languages
> use a different operator for initialization?)

Yes, Algol68.

My Algol68 is more than rusty, but:

Declare a name 'pi' to represent 3.1415926, i.e. declare a constant:

    REAL pi = 3.1415926;
    
Declare a name 'x' to represent a local variable, and assign it a value:

    REF REAL x = LOC REAL;
    x := 3.1415926;

Shorthand for the above:

   REAL x;
   x := 3.1415926;

or even:

   REAL x := pi;

Initialisation uses '=', assignment uses ':='. Note that the constant is 
defined as a real and initialised with one, but the variable is a reference 
to a real and initialised with a storage location. The last example is not 
initialising x with the value, it is implicitly initialising x with a 
location then assigning the value into that location.

-- 
Duncan Booth                                             duncan at rcp.co.uk
int month(char *p){return(124864/((p[0]+p[1]-p[2]&0x1f)+1)%12)["\5\x8\3"
"\6\7\xb\1\x9\xa\2\0\4"];} // Who said my code was obscure?