I'd like a function AnyTrue[expr,{i,{i1,i2,...}}]
which checks if expr
is True
for any of i1,i2...
It should be as if AnyTrue
was Table
followed by Or@@%
, with the difference that it only evaluates expr
until first True
is found.
Short-circuiting part is optional, what I'd really like to know is the proper way to emulate Table
's non-standard evaluation sequence.
Update 11/14
Here's a solution due to Michael, you can use it to chain "for all" and "there exists" checks
SetAttributes[AllTrue, HoldAll];
SetAttributes[AnyTrue, HoldAll];
AllTrue[{var_Symbol, lis_List}, expr_] :=
LengthWhile[lis,
TrueQ[ReleaseHold[Hold[expr] /. HoldPattern[var] -> #]] &] ==
Length[lis];
AnyTrue[{var_Symbol, lis_List}, expr_] :=
LengthWhile[lis,
Not[TrueQ[ReleaseHold[Hold[expr] /. HoldPattern[var] -> #]]] &] <
Length[lis];
AllTrue[{a, {1, 3, 5}}, AnyTrue[{b, {2, 4, 5}}, EvenQ[a + b]]]
AnyTrue[{a, {1, 3, 5}}, AllTrue[{b, {2, 4, 5}}, EvenQ[a + b]]]
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