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| author | Sebastian Graf <sebastian.graf@kit.edu> | 2020-08-26 18:50:30 +0200 |
|---|---|---|
| committer | Marge Bot <ben+marge-bot@smart-cactus.org> | 2020-09-10 10:35:33 -0400 |
| commit | 1207576ac0cfdd3fe1ea00b5505f7c874613451e (patch) | |
| tree | 33acda217dadd8e5eaa38f55f19a6ce6be54dd6f /compiler/GHC/Tc/Types.hs | |
| parent | 67ce72da1689058cb689ffbb6fcbd5cd12af56df (diff) | |
| download | haskell-1207576ac0cfdd3fe1ea00b5505f7c874613451e.tar.gz | |
PmCheck: Big refactor using guard tree variants more closely following source syntax (#18565)
Previously, we desugared and coverage checked plain guard trees as
described in Lower Your Guards. That caused (in !3849) quite a bit of
pain when we need to partially recover tree structure of the input
syntax to return covered sets for long-distance information, for
example.
In this refactor, I introduced a guard tree variant for each relevant
source syntax component of a pattern-match (mainly match groups, match,
GRHS, empty case, pattern binding). I made sure to share as much
coverage checking code as possible, so that the syntax-specific checking
functions are just wrappers around the more substantial checking
functions for the LYG primitives (`checkSequence`, `checkGrds`).
The refactoring payed off in clearer code and elimination of all panics
related to assumed guard tree structure and thus fixes #18565.
I also took the liberty to rename and re-arrange the order of functions
and comments in the module, deleted some dead and irrelevant Notes,
wrote some new ones and gave an overview module haddock.
Diffstat (limited to 'compiler/GHC/Tc/Types.hs')
| -rw-r--r-- | compiler/GHC/Tc/Types.hs | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/compiler/GHC/Tc/Types.hs b/compiler/GHC/Tc/Types.hs index b782dceee8..5111dbbe3d 100644 --- a/compiler/GHC/Tc/Types.hs +++ b/compiler/GHC/Tc/Types.hs @@ -323,7 +323,7 @@ data DsLclEnv = DsLclEnv { dsl_meta :: DsMetaEnv, -- Template Haskell bindings dsl_loc :: RealSrcSpan, -- To put in pattern-matching error msgs - -- See Note [Note [Type and Term Equality Propagation] in "GHC.HsToCore.PmCheck" + -- See Note [Note [Long-distance information] in "GHC.HsToCore.PmCheck" -- The set of reaching values Deltas is augmented as we walk inwards, -- refined through each pattern match in turn dsl_deltas :: Deltas |