On 11/1/2014 1:33 PM, bearophile wrote:
Walter Bright:
D is better here, because it doesn't introduce magically named variables.
I agree that the implicit variable is not good.
* D does the check function thing using compile time function execution to
check template arguments.
This is not nearly enough. I have written a lot about this.
I don't agree. Compile time checking can only be done on compile time arguments
(obviously) and template functions can arbitrarily check compile time arguments.
I know you've suggested extensive data flow analysis, but Jonathan's language
doesn't do that at all and he neither mentioned nor alluded to the concept of that.
* D also has full compile time function execution - it's a very heavily used
feature. It's mainly used for metaprogramming, introspection, checking of
template arguments, etc. Someone has written a ray tracer that runs at compile
time in D. D's compile time execution doesn't go as far as running external
functions in DLLs.
His "compile time execution" is different and probably better: the whole
language is available because it uses an intermediate bytecode. This makes it
more flexible and avoids the need of having essentially two different
implementations of the language.
He has two implementations - a bytecode interpreter, and a C code generator.
D's CTFE restrictions are:
1. no global variables
2. no pointer math
3. no external code execution
While this prevents you from running space invaders at compile time, I haven't
seen much of any practical limitation for things that CTFE is used for.
The ascii_map function will work, however.
The ASCII map example doesn't work in D because of reasons I have explained a
lot in past posts.
Like what?
