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Which type should numeric operations use?
Currently, it works like this:
byte a = 250
byte b = 10
...
byte x = (a + b) - 20 # this overflows, because a+b is computed as a byte
And this is actually inefficient, because the operation would most likely be
performed using 32 or even 64 bit registers. The exception is when the
temporary variable for (a+b) is spilled to stack.
Comparison to other languages
-----------------------------
C (from reading the ANSI C spec):
- performs operations as int or a larger type
- promotes to the largest operand (appears to not care about the result type)
- unsigned wins when there are operands with mixed signedness
Rust (from reading random blogs):
- all integer literals need to have a suffix, e.g. u8
(except for the default, which I think is int?)
- all casts, even narrowing ones, have to be explicit
FreePascal (don't remember this exactly):
- Promotes to Int64 in mixed-sign comparisons
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