weigh

Measure allocations of a Haskell functions/values

Version on this page:	0.0.16
LTS Haskell 24.41:	0.0.18
Stackage Nightly 2026-05-19:	0.0.18
Latest on Hackage:	0.0.18

See all snapshots weigh appears in

BSD-3-Clause licensed by Chris Done

Maintained by [email protected]

This version can be pinned in stack with:weigh-0.0.16@sha256:da118318d2211b325e7d6cd3729810729eb8f275e938e7113d0a4d3c51cdec29,1155

Module documentation for 0.0.16

Weigh

Depends on 7 packages(full list with versions):

base, deepseq, ghc, mtl, process, split, temporary

Used by 1 package in lts-16.11(full list with versions):

xeno

weigh

Measures the memory usage of a Haskell value or function

Limitations

:warning: Turn off the -threaded flag, otherwise it will cause inconsistent results.

Example use

import Weigh

main :: IO ()
main =
  mainWith
    (do func "integers count 0" count 0
        func "integers count 1" count 1
        func "integers count 10" count 10
        func "integers count 100" count 100)
  where
    count :: Integer -> ()
    count 0 = ()
    count a = count (a - 1)

Output results:

Case	Allocated	GCs
integers count 0	16	0
integers count 1	88	0
integers count 10	736	0
integers count 100	7,216	0

Output by default is plain text table; pass --markdown to get a markdown output like the above.