Indeed it could :-) It's almost certainly like that because a let got introduced into calc by an earlier stage of the compiler. In fact any code involving a let-introduced variable that isn't used in more than once place could be simplified by substituting the variable for it's definition. For example: let x = foo 10 in bar x will generate less instructions as: bar (foo 10) But since it doesn't save a huge amount I deemed it not worth the effort needed to detect unshared let introduced variables and remove them :-) Thanks Tom On Thu, 2006-09-28 at 01:38 +0530, Kartik Vaddadi wrote:

Hello, I compiled the following program using yhc:

...

main = print (calc 3) calc x = munge x 6 munge x y = x

The bytecode for calc starts with:

NEED_HEAP_1 PUSH_CONST_0 PUSH_CONST_1 PUSH_ZAP_1

Couldn't this be simplified to: NEED_HEAP_1 PUSH_CONST_1 PUSH_CONST_0

Thanks.