From d9ed708bb5d22cf61029eac0a23b9d3dc94a5146 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Mon, 2 Feb 2015 15:31:36 +0100 Subject: Do not convert map patterns to map expressions In code such as: case {a,Map} of {a,#{}}=T -> T end we must NOT rewrite a map pattern to a map expression like this: case Map of #{} -> {a,#{}} end because the pattern '#{}' will match any map, but the expression '#{}' will construct an empty map. --- lib/compiler/test/match_SUITE.erl | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'lib/compiler/test') diff --git a/lib/compiler/test/match_SUITE.erl b/lib/compiler/test/match_SUITE.erl index e5aaf49d6f..1e778dca24 100644 --- a/lib/compiler/test/match_SUITE.erl +++ b/lib/compiler/test/match_SUITE.erl @@ -406,12 +406,19 @@ underscore(Config) when is_list(Config) -> match_map(Config) when is_list(Config) -> Map = #{key=>{x,y},ignore=>anything}, #s{map=Map,t={x,y}} = do_match_map(#s{map=Map}), + {a,#{k:={a,b,c}}} = do_match_map_2(#{k=>{a,b,c}}), ok. do_match_map(#s{map=#{key:=Val}}=S) -> %% Would crash with a 'badarg' exception. S#s{t=Val}. +do_match_map_2(Map) -> + case {a,Map} of + {a,#{k:=_}}=Tuple -> + Tuple + end. + coverage(Config) when is_list(Config) -> %% Cover beam_dead. ok = coverage_1(x, a), -- cgit v1.2.3