PROPOSAL: Unsigned Integer Widening Operator (original) (raw)

Bruce Chapman brucechapman at paradise.net.nz
Thu Mar 26 02:15:25 PDT 2009

Noel Grandin wrote:

I would think that a utility class that performed widening operations, and maybe some other useful stuff would be preferable to extending the language/

Perhaps a BinaryMath class to live alongside java.lang.Math? Regards, Noel.

There is some truth to that. BUT on the other side of the ledger there are two operators that add extra bits to the left of a value. Right shift has two forms, one to sign extend and one to zero extend, whereas widening only has a sign extend form of the operator (which is the unary

Also it is worth considering that the zero extend widening operator is (hopefully) sufficiently succinct, and gives the impression of being sufficiently cheap that the perceived wisdom for effective unsigned byte manipulation might become to always apply the operator to variable and array accesses. This would reduce bugs. I don't think a method call would have that same subconscious effect. You'd tend to only use the method where it was actually needed, and you'd sometimes get that decision wrong.

Bruce

Bruce Chapman wrote:

Title Unsigned Integer Widening Operator

latest html version at http://docs.google.com/Doc?id=dcvp3mkv2k39wt5gf&hl AUTHOR(S): Bruce Chapman OVERVIEW

FEATURE SUMMARY: Add an unsigned widening operator to convert bytes (in particular), shorts, and chars (for completeness) to int while avoiding sign extension.

SNIP

More information about the coin-dev mailing list