[Haskell-cafe] Byte Histogram

[Richard O'Keefe]

On 4/02/2011, at 8:26 PM, Johan Tibell wrote:

> --show-iface HI_FILE

sort.hs has 50 top level functions.
One of them is main, and the others are all reachable from it.

ghc -O sort.hs
ghc --show-iface sort.hi

The only functions listed are variants of main.
Dropping -O leaves one variant of main only;
the other 49 functions have disappeared.

It is, by the way, something of a nuisance that if you do
	ghc sort.hs
	...
	ghc -O sort.hs
it insists "compilation NOT required" despite the fact that
the previous compilation was with materially *different* options.
(GHC 6.12.3)

Given this clue I was able to get the information I wanted by
exporting all the functions.

This is the wrong interface.  If a programmer is concerned that
strictness analysis might not be finding something they thought
was strict, they would ideally like to have *all* the functions
reported, but at a minimum, all of the top level functions.