[Mono-dev] [PATCH] The big "as" cast cleanup

Juraj Skripsky js at hotfeet.ch
Tue Jan 8 08:49:42 EST 2008


After getting annoyed by NullReferenceExceptions which turned out to be
ClassCastExceptions in disguise, I've decided to clean up the code in
mcs/class/corlib with regard to wrong/unnecessary uses of the "as" cast

Reasons for the clean up:
- NullRefExceptions are thrown where ClassCastException should be. With
explicit casts, the later is thrown at the right spot and gives you more
- Personally, I consider the use of the "as" operator to be confusing /
irritating in those cases where a explicit cast is sufficient.

The following links also describe the problems with the "as" operator:

The performance of explicit casts and "as" casts are pretty much the
same on Mono and MS.NET (see and run attached test program).

Attached is a patch (including ChangeLog entries).
All unit tests pass.

Please review.

- Juraj
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