hlibsass-0.1.5.0: libsass/src/bind.cpp
#include "bind.hpp"
#include "ast.hpp"
#include "context.hpp"
#include "eval.hpp"
#include <map>
#include <iostream>
#include <sstream>
#include "to_string.hpp"
namespace Sass {
void bind(std::string type, std::string name, Parameters* ps, Arguments* as, Context* ctx, Env* env, Eval* eval)
{
std::string callee(type + " " + name);
Listize listize(*ctx);
std::map<std::string, Parameter*> param_map;
for (size_t i = 0, L = as->length(); i < L; ++i) {
if (auto str = dynamic_cast<String_Quoted*>((*as)[i]->value())) {
// force optional quotes (only if needed)
if (str->quote_mark()) {
str->quote_mark('*');
str->is_delayed(true);
}
}
}
// Set up a map to ensure named arguments refer to actual parameters. Also
// eval each default value left-to-right, wrt env, populating env as we go.
for (size_t i = 0, L = ps->length(); i < L; ++i) {
Parameter* p = (*ps)[i];
param_map[p->name()] = p;
// if (p->default_value()) {
// env->local_frame()[p->name()] = p->default_value()->perform(eval->with(env));
// }
}
// plug in all args; if we have leftover params, deal with it later
size_t ip = 0, LP = ps->length();
size_t ia = 0, LA = as->length();
while (ia < LA) {
Argument* a = (*as)[ia];
if (ip >= LP) {
// skip empty rest arguments
if (a->is_rest_argument()) {
if (List* l = dynamic_cast<List*>(a->value())) {
if (l->length() == 0) {
++ ia; continue;
}
}
}
std::stringstream msg;
msg << "wrong number of arguments (" << LA << " for " << LP << ")";
msg << " for `" << name << "'";
return error(msg.str(), as->pstate());
}
Parameter* p = (*ps)[ip];
// If the current parameter is the rest parameter, process and break the loop
if (p->is_rest_parameter()) {
// The next argument by coincidence provides a rest argument
if (a->is_rest_argument()) {
// We should always get a list for rest arguments
if (List* rest = dynamic_cast<List*>(a->value())) {
// arg contains a list
List* args = rest;
// make sure it's an arglist
if (rest->is_arglist()) {
// can pass it through as it was
env->local_frame()[p->name()] = args;
}
// create a new list and wrap each item as an argument
// otherwise we will not be able to fetch it again
else {
// create a new list object for wrapped items
List* arglist = SASS_MEMORY_NEW(ctx->mem, List,
p->pstate(),
0,
rest->separator(),
true);
// wrap each item from list as an argument
for (Expression* item : rest->elements()) {
(*arglist) << SASS_MEMORY_NEW(ctx->mem, Argument,
item->pstate(),
item,
"",
false,
false);
}
// assign new arglist to environment
env->local_frame()[p->name()] = arglist;
}
}
// invalid state
else {
throw std::runtime_error("invalid state");
}
} else if (a->is_keyword_argument()) {
// expand keyword arguments into their parameters
List* arglist = SASS_MEMORY_NEW(ctx->mem, List, p->pstate(), 0, SASS_COMMA, true);
env->local_frame()[p->name()] = arglist;
Map* argmap = static_cast<Map*>(a->value());
for (auto key : argmap->keys()) {
std::string name = unquote(static_cast<String_Constant*>(key)->value());
(*arglist) << SASS_MEMORY_NEW(ctx->mem, Argument,
key->pstate(),
argmap->at(key),
"$" + name,
false,
false);
}
} else {
// create a new list object for wrapped items
List* arglist = SASS_MEMORY_NEW(ctx->mem, List,
p->pstate(),
0,
SASS_COMMA,
true);
// consume the next args
while (ia < LA) {
// get and post inc
a = (*as)[ia++];
// maybe we have another list as argument
List* ls = dynamic_cast<List*>(a->value());
// skip any list completely if empty
if (ls && ls->empty() && a->is_rest_argument()) continue;
// flatten all nested arglists
if (ls && ls->is_arglist()) {
for (size_t i = 0, L = ls->size(); i < L; ++i) {
// already have a wrapped argument
if (Argument* arg = dynamic_cast<Argument*>((*ls)[i])) {
(*arglist) << SASS_MEMORY_NEW(ctx->mem, Argument, *arg);
}
// wrap all other value types into Argument
else {
(*arglist) << SASS_MEMORY_NEW(ctx->mem, Argument,
(*ls)[i]->pstate(),
(*ls)[i],
"",
false,
false);
}
}
}
// already have a wrapped argument
else if (Argument* arg = dynamic_cast<Argument*>(a->value())) {
(*arglist) << SASS_MEMORY_NEW(ctx->mem, Argument, *arg);
}
// wrap all other value types into Argument
else {
(*arglist) << SASS_MEMORY_NEW(ctx->mem, Argument,
a->pstate(),
a->value(),
a->name(),
false,
false);
}
// check if we have rest argument
if (a->is_rest_argument()) {
// preserve the list separator from rest args
if (List* rest = dynamic_cast<List*>(a->value())) {
arglist->separator(rest->separator());
}
// no more arguments
break;
}
}
// assign new arglist to environment
env->local_frame()[p->name()] = arglist;
}
// consumed parameter
++ip;
// no more paramaters
break;
}
// If the current argument is the rest argument, extract a value for processing
else if (a->is_rest_argument()) {
// normal param and rest arg
List* arglist = static_cast<List*>(a->value());
// empty rest arg - treat all args as default values
if (!arglist->length()) {
break;
} else {
if (arglist->length() + ia > LP && !ps->has_rest_parameter()) {
int arg_count = (arglist->length() + LA - 1);
std::stringstream msg;
msg << callee << " takes " << LP;
msg << (LP == 1 ? " argument" : " arguments");
msg << " but " << arg_count;
msg << (arg_count == 1 ? " was passed" : " were passed.");
deprecated_bind(msg.str(), as->pstate());
}
}
// otherwise move one of the rest args into the param, converting to argument if necessary
if (!(a = dynamic_cast<Argument*>((*arglist)[0]))) {
Expression* a_to_convert = (*arglist)[0];
a = SASS_MEMORY_NEW(ctx->mem, Argument,
a_to_convert->pstate(),
a_to_convert,
"",
false,
false);
}
arglist->elements().erase(arglist->elements().begin());
if (!arglist->length() || (!arglist->is_arglist() && ip + 1 == LP)) {
++ia;
}
} else if (a->is_keyword_argument()) {
Map* argmap = static_cast<Map*>(a->value());
for (auto key : argmap->keys()) {
std::string name = "$" + unquote(static_cast<String_Constant*>(key)->value());
if (!param_map.count(name)) {
std::stringstream msg;
msg << callee << " has no parameter named " << name;
error(msg.str(), a->pstate());
}
env->local_frame()[name] = argmap->at(key);
}
++ia;
continue;
} else {
++ia;
}
if (a->name().empty()) {
if (env->has_local(p->name())) {
std::stringstream msg;
msg << "parameter " << p->name()
<< " provided more than once in call to " << callee;
error(msg.str(), a->pstate());
}
// ordinal arg -- bind it to the next param
env->local_frame()[p->name()] = a->value();
++ip;
}
else {
// named arg -- bind it to the appropriately named param
if (!param_map.count(a->name())) {
std::stringstream msg;
msg << callee << " has no parameter named " << a->name();
error(msg.str(), a->pstate());
}
if (param_map[a->name()]->is_rest_parameter()) {
std::stringstream msg;
msg << "argument " << a->name() << " of " << callee
<< "cannot be used as named argument";
error(msg.str(), a->pstate());
}
if (env->has_local(a->name())) {
std::stringstream msg;
msg << "parameter " << p->name()
<< "provided more than once in call to " << callee;
error(msg.str(), a->pstate());
}
env->local_frame()[a->name()] = a->value();
}
}
// EO while ia
// If we make it here, we're out of args but may have leftover params.
// That's only okay if they have default values, or were already bound by
// named arguments, or if it's a single rest-param.
for (size_t i = ip; i < LP; ++i) {
To_String to_string(ctx);
Parameter* leftover = (*ps)[i];
// cerr << "env for default params:" << endl;
// env->print();
// cerr << "********" << endl;
if (!env->has_local(leftover->name())) {
if (leftover->is_rest_parameter()) {
env->local_frame()[leftover->name()] = SASS_MEMORY_NEW(ctx->mem, List,
leftover->pstate(),
0,
SASS_COMMA,
true);
}
else if (leftover->default_value()) {
Expression* dv = leftover->default_value()->perform(eval);
env->local_frame()[leftover->name()] = dv;
}
else {
// param is unbound and has no default value -- error
std::stringstream msg;
msg << "required parameter " << leftover->name()
<< " is missing in call to " << callee;
error(msg.str(), as->pstate());
}
}
}
return;
}
}