[comp.lang.misc] Algol-style assignment operators

alderson@Jessica.stanford.edu (Rich Alderson) (12/22/88)

In article <2185@eos.UUCP> eugene@eos.UUCP (Eugene Miya) writes:

>On ":=" versus "=": Altos had an backward arrow assignment key, not "<-" for
>Mesa.  (this could correspond to other language arrows (UP) ^ and (RIGHT)
>"->".)  Just standardize some extra characters.  8-) It will never happen.

The original Algol specification was for TWO languages: The one most people
think of as Algol 60 was intended as the machine-readable version, using
current ("IBM") keypunches.  The other, intended for algorithm specification in
print, used a different character set.

Specifically, the assignment operator in the latter was an arrow pointing to
the left.  The two-character form ":=" was chosen to disambiguate assignment
from the Boolean equality operator "=".