JP Moresmau | 24 Jan 16:38 2014

Why is the Show instance of Text not used by showTerm?

Hello cafe, I'm continuing my adventures with the GHC API. I'm following the code given at to run statements like in GHCi, but the behavior sometimes puzzles me.

If I load a simple module:

module Test where
import qualified Data.Text as T

And then run the statement T.pack \"test\", I expect to see "test" back. But I get Data.Text.Internal.Text _ 0 4. If I run "show $ T.Pack \"test\"" I get the expected result. Text _ 0 4 seems to be the output of the showText debugging function in Data.Text, that I don't see used in the Show instance. And looking at the GHC code (Debugger.hs) it does perform a show of the expression given. Why doesn't it work? What subtlety am I missing?



JP Moresmau
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