context-free grammar
Simon Buerger
krox at gmx.net
Fri Mar 4 17:05:57 PST 2011
It is often said that D's grammar is easier to parse than C++, i.e. it
should be possible to seperate syntactic and semantic analysis, which
is not possible in C++ with the template-"< >" and so on. But I found
following example:
The Line "a * b = c;" can be interpreted in two ways:
-> Declaration of variable b of type a*
-> (a*b) is itself a lvalue which is assigned to.
Current D (gdc 2.051) interprets it always in the first way and yields
an error if the second is meant. The Workaround is simply to use
parens like "(a*b)=c", so it's not a real issue. But at the same time,
C++ (gcc 4.5) has no problem to distinguish it even without parens.
So, is the advertising as "context-free grammar" wrong?
- Krox
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