/* parse symbols out of tokens */
int semanter_reduce(list_t *stack, list_t *partial) {
size_t funcparams = 0;
token_t *op;
while ((op = (token_t*)list_pop(stack))) {
switch (op->lexcomp) {
/* binary operators */
case tokPlus : case tokMinus : case tokTimes :
case tokDivide : case tokModulo : case tokPower : case tokUnaryMinus :
case tokRShift : case tokLShift : case tokBitAnd :
case tokBitOr : case tokBitXor : case tokBitNot :
case tokAnd : case tokOr : case tokNot :
case tokEq : case tokNe : case tokGt :
case tokLt : case tokGe : case tokLe :
list_push(partial, symbol_operator(op->lexcomp));
break;
case tokNumber:
list_push(partial, symbol_number(strtold(op->lexem, NULL)));
break;
case tokTrue:
list_push(partial, symbol_number(1.0));
break;
case tokFalse:
list_push(partial, symbol_number(0.0));
break;
case tokId:
list_push(partial, symbol_variable(op->lexem));
break;
case tokFunction:
list_push(partial, symbol_function(op->lexem, funcparams));
break;
/* ignore these, no semantic value */
case tokComma : case tokStackEmpty : case tokNoMatch :
case tokCMango : case tokOParen : case tokCParen :
case tokAsign : case tokText:
break;
case tokEMango:
funcparams++;
break;
/* reduction done */
case tokOMango:
return 0;
}
}
return 0;
}
LISPTR apply(LISPTR f, LISPTR args)
{
if (symbolp(f)) {
// get the function binding of f
f = symbol_function(f);
if (consp(f)) {
// function defined as S-expr
if (car(f) == LAMBDA) {
LISPTR oldBindings = lexvars;
// bind formal arguments to evaluated actual arguments:
lexvars = bind_args(cadr(f), args, lexvars);
f = progn(cddr(f));
lexvars = oldBindings;
}
} else if (compiled_function_p(f)) {
// call compiled function with args
f = call_compiled_fn(f, args);
}
}
return f;
}
