[Haskell-beginners] Testing a data structure, etc

Stephen Tetley stephen.tetley at gmail.com
Sat Jun 19 10:43:32 EDT 2010

Hi Matthew

A quick one to reduce line width is to import qualified with a single
character alias:

import qualified Data.Map as M

Then the longest line becomes:

   Nothing -> SequenceMap notP (M.insert a (insert as p empty) M.empty)

... saving 2x7 characters in this case.

As for performance always compile (never use GHCi) and always use -O2
otherwise rewrite-rules and other optimizations will not be used by

When you run the executable, get the runtime system to print its stats:

./MyProg +RTS -sstderr -RTS

... This will print memory usage, garbage collection and timing stats.
For serious work there is also the Criterion bench-marking package.

Best wishes


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