diff options
Diffstat (limited to 'src/interp/c-util.boot')
| -rw-r--r-- | src/interp/c-util.boot | 28 |
1 files changed, 27 insertions, 1 deletions
diff --git a/src/interp/c-util.boot b/src/interp/c-util.boot index 05915075..5820b091 100644 --- a/src/interp/c-util.boot +++ b/src/interp/c-util.boot @@ -441,13 +441,39 @@ getSuccessEnvironment(a,e) == symbol? a and (T := get(a,"value",e)) => getSuccessEnvironment(T.expr,e) e +isUnionMode(m,e) == + m is ["Union",:.] => m + v := get(RepIfRepHack m,"value",e) => + (v.expr is ["Union",:.] => v.expr; nil) + nil + +++ Return the UnionCategory of `m' in the environment `e', if known. +unionLike?(m,e) == + isUnionMode(m,e) is ['Union,:branches] => ['UnionCategory,:branches] + -- Take a cheap approximation at domains with Union-like flavour. + T := compForMode(m,$EmptyMode,e) or return nil + T.expr is ['Union,:branches] => ['UnionCategory,:T.expr.args] + T.mode is ['UnionCategory,:.] => T.mode + T.mode is ['UnionType] => ['UnionCategory] + T.mode isnt ['Join,:cats,['CATEGORY,.,:sigs]] => nil + member(['UnionType],cats) => + ['UnionCategory, + :[b for ['SIGNATURE,"case",[=$Boolean,'$,["[||]",b]]] in sigs]] + nil + +++ If `x' designates a store with multiple views, e.g. Union, return +++ the collection of those modes. +unionProperty(x,e) == + atom x => unionLike?(getmode(x,e),e) + nil + getInverseEnvironment(a,e) == a is ["case",x,m] and (x := lhsOfAssignment x) and IDENTP x => --the next two lines are necessary to get 3-branched Unions to work -- old-style unions, that is (get(x,"condition",e) is [["OR",:oldpred]]) and member(a,oldpred) => put(x,"condition",[MKPF(delete(a,oldpred),"OR")],e) - getUnionMode(x,e) is ["Union",:l] => + unionProperty(x,e) is ['UnionCategory,:l] => l':= delete(m,l) for u in l' repeat if u is ['_:,=m,:.] then l':= delete(u,l') |