factor/library/compiler/inference/inference.facts

IN: inference
USING: help kernel ;

HELP: inference-error "( msg -- )"
{ $values { "msg" "an object" } }
{ $description "Throws an " { $link inference-error } "." }
{ $error-description
    "Thrown by " { $link infer } " when the stack effect of a quotation cannot be inferred. There are several possible reasons that this can occur:"
    { $list
        { "The quotation applies " { $link call } " or " { $link if } " to quotation values which are not literals; thus the potential stack effect is arbitrary" }
        "The quotation involves conditionals where the branches have incompatible stack effects"
        "The quotation calls a recursive word with no base case"
    }
    "Words without a static stack effect cannot be compiled, but will still run in the interpreter."
} ;

HELP: infer "( quot -- effect )"
{ $values { "quot" "a quotation" } { "effect" "a pair of integers" } }
{ $description "Attempts to infer the quotation's stack effect, outputting a pair holding the correct of data stack inputs and outputs for the quotation." }
{ $errors "Throws an error if stack effect inference fails." } ;