Re: Parsing/evaluating shortcutting operators

"Jeremy J Starcher" <r3jjs@yahoo.com> wrote in message
news:09-01-032@comp.compilers...


> I am unsure how to proceed in setting up shortcutting operators
> however. For example, this code:
>
> declare boolean b
>
> b = (1 == 2) || (3 == 4)
>
> Which results in the expression
> 1 2 == 3 4 == || b =


You've made me feel inadequate, because my compiler only uses shortcut
evaluation when there are jumps involved (eg. inside an If conditional, but
not in an ordinary expression).


But I found that my (a|b|c) construct (equivalent to C's a?b:c) generates
code like an If statement.


So I can fix this 'problem' by turning 'a and b' into (a and b|1|0), and 'a
or b' into (a or b|1|0), either manually or letting the compile do it as you
seem to be attempting to.


It's possible that you can try something similar, if you also have an
equivalent a?b:c operator that already has short-circuit evaluation.


--
bartc

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