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| author | Ben Gamari <bgamari.foss@gmail.com> | 2017-07-20 19:24:00 -0400 |
|---|---|---|
| committer | Ben Gamari <ben@smart-cactus.org> | 2017-07-20 19:24:01 -0400 |
| commit | 36e8bcba08446dbc4e7532ef9db5517c13977bf9 (patch) | |
| tree | 4b46040211993cd0a6f21c50a3bae6c8b9929570 /compiler/hsSyn/HsPat.hs | |
| parent | ccac387bd90da8e1b6998e8480897a0bf0694310 (diff) | |
| download | haskell-36e8bcba08446dbc4e7532ef9db5517c13977bf9.tar.gz | |
HsPat: Assume that no spliced patterns are irrefutable
This is a conservative assumption which will limit some uses of spliced
patterns, but it fixes #13984.
Test Plan: Validate
Reviewers: RyanGlScott, AaronFriel, austin
Reviewed By: RyanGlScott
Subscribers: rwbarton, thomie
GHC Trac Issues: #13984
Differential Revision: https://phabricator.haskell.org/D3766
Diffstat (limited to 'compiler/hsSyn/HsPat.hs')
| -rw-r--r-- | compiler/hsSyn/HsPat.hs | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/compiler/hsSyn/HsPat.hs b/compiler/hsSyn/HsPat.hs index 93ad9ec383..f7d18768df 100644 --- a/compiler/hsSyn/HsPat.hs +++ b/compiler/hsSyn/HsPat.hs @@ -620,7 +620,7 @@ isIrrefutableHsPat pat go1 (SigPatOut pat _) = go pat go1 (TuplePat pats _ _) = all go pats go1 (SumPat pat _ _ _) = go pat - go1 (ListPat {}) = False + go1 (ListPat {}) = False go1 (PArrPat {}) = False -- ? go1 (ConPatIn {}) = False -- Conservative @@ -632,15 +632,13 @@ isIrrefutableHsPat pat go1 (ConPatOut{ pat_con = L _ (PatSynCon _pat) }) = False -- Conservative - go1 (LitPat {}) = False - go1 (NPat {}) = False - go1 (NPlusKPat {}) = False + go1 (LitPat {}) = False + go1 (NPat {}) = False + go1 (NPlusKPat {}) = False - -- Both should be gotten rid of by renamer before - -- isIrrefutablePat is called - go1 (SplicePat {}) = urk pat - - urk pat = pprPanic "isIrrefutableHsPat:" (ppr pat) + -- We conservatively assume that no TH splices are irrefutable + -- since we cannot know until the splice is evaluated. + go1 (SplicePat {}) = False hsPatNeedsParens :: Pat a -> Bool hsPatNeedsParens (NPlusKPat {}) = True |