ALGOL W
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Algol-W is a programming language. It was Niklaus Wirth's proposal for a successor to ALGOL 60 in the ALGOL 68 committee.
Algol-W is clearly a transitionary stage between ALGOL 60 and Pascal (created later by Wirth also). It represented a relatively conservative modification of ALGOL 60; to ALGOL 60 Wirth added string, bitstring, complex number and reference to record datatypes and a call-by-result parameter passing mechanism but changed little else.
Like the rest of Wirth's languages (Pascal, Modula-2, Oberon, etc.), Algol-W is small and statically typed. The language that eventually became ALGOL 68 is much larger and more complex than Algol-W, and it differs more from Algol 60 than Algol-W does.
Code Sample
record PERSON (
string NAME;
integer AGE;
logical MALE;
reference(PERSON) FATHER, MOTHER, YOUNGESTOFFSPRING, ELDERSIBLING
);
reference(PERSON) procedure YOUNGESTUNCLE (reference(PERSON) R);
begin
reference(PERSON) P, M;
P := YOUNGESTOFFSPRING(FATHER(FATHER(R)));
while (P ¬= null) and (¬ MALE(P)) or (P = FATHER(R)) do
P := ELDERSIBLING(P);
M := YOUNGESTOFFSPRING(MOTHER(MOTHER(R)));
while (M ¬= null) and (¬ MALE(M)) do
M := ELDERSIBLING(M);
if P = null then
M
else if M = null then
P
else
if AGE(P) < AGE(M) then P else M
end
External References
Stanford Computer Science Department Technical Report CS-TR-68-89 (http://www-db.stanford.edu/TR/CS-TR-68-89.html) Various documents for Stanford University's 1972 implementation of Algol-W. The report includes the Algol W Language Description.