Enforce tryFind & alike methods as in #1212
Enforce tryFind & alike methods as in #1212

fable-compiler/Fable,ncave/Fable,ncave/Fable,fable-compiler/Fable,ncave/Fable,ncave/Fable,inosik/Fable,fable-compiler/Fable,fable-compiler/Fable,ncave/Fable,fable-compiler/Fable,inosik/Fable,fable-compiler/Fable,fable-compiler/Fable,ncave/Fable,ncave/Fable