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    • Check-safe-expressions

    Check-safe-expression

    Check if an expression is safe.

    Signature
    (check-safe-expression expr varset funtab) → results?
    Arguments
    expr — Guard (expressionp expr).
    varset — Guard (identifier-setp varset).
    funtab — Guard (funtablep funtab).
    Returns
    results? — Type (nat-resultp results?).

    If successful, return the number of values that the expression yields. Otherwise, return an error.

    A path always yields one result.

    A literal's safety is independent from the variables in scope. A literal always returns one result.