Michael Van Canneyt wrote:
On Fri, 9 Oct 2015, Sven Barth wrote:
Am 08.10.2015 23:48 schrieb "Michael Van Canneyt"
<mich...@freepascal.org>:
Actually, yes I think C's or Javascript's ternary is better suited.
Let me explain. If I see
If expr1 then expr2 else expr3
it says 'statement' to me. But
a ? b : c;
Says "expression" to me.
So
left := a ? b : c;
That's probably only because other languages use that as the ternary.
No, it is because there are no keywords involved.
The keyword "If" starts a statement. It's a simple rule.
As I said: by using "if" in an expression, you break the rule and
introduce ambiguity.
There also another reason why I prefer the variant with the if: ease to
implement in the compiler.
For the if one merely needs to add a corresponding case in factor() while
for the ?: one needs to fiddle with the compiler's operator precedence
rules that are applied in sub_expr() which can lead to desaster either
during implementation or later on when bugs are discovered...
I don't see how the use of "if" differs from "?" in rules of precedence,
they are at the exact same level.
They're both just tokens to the compiler. At least "?" has the advantage
of being new and not yet used, so is unambiguously.
Jonas, what's your take on this as an overall language guru?
--
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk
[Opinions above are the author's, not those of his employers or colleagues]
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