Recursive functions need to be made lazy

[paf31]

foo = foo compiles but gives a runtime error foo is not defined

[paf31]

Potential solution: for function types at the top level, generate code of the form:

function foo(args) {
    return body;
}

instead of

foo = function(args) {
    return body;
};

For all other types, do not allow recursion. The user can add explicit laziness in the form of \ -> ... if other types need to be made recursive.