Andrei Alexandrescu:
http://www.reddit.com/r/programming/comments/1yts5n/facebook_open_sources_flint_a_c_linter_written_in/
3. Reserved identifiers (checkDefinedNames). A C and C++ naming
rule that often gets forgotten is that all identifiers starting
with an underscore followed by an uppercase letter, plus all
identifiers containing two consecutive underscores, are reserved
by the implementation. (Of course there are exceptions to the
rule in our code, such as _GNU_SOURCE or _XOPEN_SOURCE, which is
why flint keeps aside a whitelist while checking for reserved
identifier patterns.)<
D language has similar rules, but I don't rember if the D
compiler warns against usage of similar identifiers.
8. Initializing a variable from itself
(checkInitializeFromItself). We found that people wrote
constructors like:
class X {
...
int a_;
X(const X& rhs) : a_(a_) {}
X(int a) : a_(a_) {}
};
The intent was to use a_(rhs.a_) in the first constructor and
a_(a) in the second. That hardly ever helps, and the compiler
keeps mum about it. We like to say, "There's a flint rule for
that," in order to resolve the problem.<
I'd like a similar warning in the D compiler for a similar (very)
common bug:
class Foo {
int x;
this(int x_) { this.x = x; }
}
void main() {}
16. Check against throwing new-allocated bald pointers
(checkThrowsHeapException). This eliminates the throw new T
anti-pattern.<
I don't fully understand this.
The "throw new Exception(...)" pattern in D was recently
discussed, and sometimes re-using an Exception is more efficient.
20. Pass cheap types by value (checkFollyStringPieceByValue).
Certain user-defined types, such as iterators or pair of
iterators, are small and cheap to copy so it's virtually always
better to pass them by value instead of the conservative
reference to const. Folly's StringPiece is an example - it
occupies two words and has raw copy semantics.<
In D there is about the same problem.
Additionally the D compiler doesn't warn if you do kind of the
opposite:
alias MyArr = int[5000];
void foo(MyArr x) {}
void main() {}
Bye,
bearophile
