text/plain
•
7.82 KB
•
267 lines
/* Nujel - Copyright (C) 2020-2022 - Benjamin Vincent Schulenburg
* This project uses the MIT license, a copy should be included under /LICENSE */
#ifndef NUJEL_AMALGAMATION
#include "nujel-private.h"
#endif
lTree *lTreeNew(const lSymbol *s, lVal v){
lTree *ret = lTreeAllocRaw();
ret->key = s;
ret->height = 1;
ret->value = v;
return ret;
}
static uint lTreeHeight(const lTree *t){
return t == NULL ? 0 : t->height;
}
static uint lTreeCalcHeight(const lTree *t){
return 1 + MAX(lTreeHeight(t->left),lTreeHeight(t->right));
}
/* Get the balance factor of T,
* which is used to rebalance the tree automatically during inserts */
static int lTreeGetBalance(const lTree *t){
return t == NULL ? 0 : lTreeHeight(t->left) - lTreeHeight(t->right);
}
/* Reset S to be associated to V if it has already been bound, storing TRUE in
* FOUND on success */
void lTreeSet(lTree *t, const lSymbol *s, lVal v, bool *found){
if(unlikely(t == NULL)){
return;
}else if(unlikely(s == t->key)){
t->value = v;
if(likely(found)){
*found = true;
}
}else if(s > t->key){
lTreeSet(t->right,s,v,found);
}else{
lTreeSet(t->left,s,v,found);
}
}
/* Rotate the tree X to the left, in order to balance the tree again */
static lTree *lTreeRotateLeft(lTree *x){
lTree *y = x->right;
if(y == NULL){return x;}
lTree *T2 = y->left;
y->left = x;
x->right = T2;
x->height = lTreeCalcHeight(x);
y->height = lTreeCalcHeight(y);
return y;
}
/* Rotate the tree X to the right, in order to balance the tree again */
static lTree *lTreeRotateRight(lTree *y){
lTree *x = y->left;
if(x == NULL){return y;}
lTree *T2 = x->right;
x->right = y;
y->left = T2;
x->height = lTreeCalcHeight(x);
y->height = lTreeCalcHeight(y);
return x;
}
/* Rebalance the tree T if is out of balance, S should be the last symbol that
* was inserted, which must have led to the inbalance with it's insertion */
static lTree *lTreeBalance(lTree *t, const lSymbol *s){
int balance = lTreeGetBalance(t);
if(balance < -1){
if(s < t->right->key){
t->right = lTreeRotateRight(t->right);
}
return lTreeRotateLeft(t);
}else if(balance > 1){
if(s > t->left->key){
t->left = lTreeRotateLeft(t->left);
}
return lTreeRotateRight(t);
}
return t;
}
/* Insert an association S -> V in the tree T, creating a new segment if
* necessary, otherwise the old segment will be mutated */
lTree *lTreeInsert(lTree *t, const lSymbol *s, lVal v){
if(unlikely(t == NULL)){
return lTreeNew(s,v);
}else if(unlikely(t->key == NULL)){
t->key = s;
t->value = v;
return t;
}else if(unlikely(t->key == s)){
t->value = v;
return t;
}else{
if(s < t->key){
t->left = lTreeInsert(t->left,s,v);
}else {
t->right = lTreeInsert(t->right,s,v);
}
t->height = lTreeCalcHeight(t);
t = lTreeBalance(t,s);
return t;
}
}
/* Get whatever value is associated in T to S,
* setting FOUND to true if successful */
lVal lTreeGet(const lTree *t, const lSymbol *s, bool *found){
const lTree *c = t;
while(likely(c)){
if(unlikely(s == c->key)){
if(likely(found != NULL)){*found = true;}
return c->value;
}
c = s > c->key ? c->right : c->left;
}
return NIL;
}
/* Return true if there is an association for S in T, storing the value
* in values, if found. */
bool lTreeHas(const lTree *t, const lSymbol *s, lVal *value){
bool found = false;
lVal v = lTreeGet(t, s, &found);
if(found && value){*value = v;}
return found;
}
/* Add all the keys within T to the beginning LIST */
static lVal lTreeAddKeysToList(const lTree *t, lVal list){
if(unlikely((t == NULL) || (t->key == NULL))){return list;}
list = lTreeAddKeysToList(t->right, list);
list = lCons(lValKeywordS(t->key), list);
return lTreeAddKeysToList(t->left, list);
}
/* Add all the values within T to the beginning LIST */
static lVal lTreeAddValuesToList(const lTree *t, lVal list){
if(unlikely((t == NULL) || (t->key == NULL))){return list;}
list = lTreeAddValuesToList(t->right, list);
list = lCons(t->value, list);
return lTreeAddValuesToList(t->left, list);
}
/* Create a list of all the keys within T */
static lVal lTreeKeysToList(const lTree *t){
return t ? lTreeAddKeysToList(t,NIL) : NIL;
}
/* Create a list of all the values within T */
static lVal lTreeValuesToList(const lTree *t){
return t ? lTreeAddValuesToList(t, NIL) : NIL;
}
/* Return the total size of the tree T */
static uint lTreeSize(const lTree *t){
return t == NULL ? 0 : (t->key ? 1 : 0) + lTreeSize(t->left) + lTreeSize(t->right);
}
/* Return a duplicate of t */
lTree *lTreeDup(const lTree *t){
if(unlikely(t == NULL)){return NULL;}
lTree *ret = lTreeAllocRaw();
ret->key = t->key;
ret->value = t->value;
ret->height = t->height;
ret->left = lTreeDup(t->left);
ret->right = lTreeDup(t->right);
return ret;
}
lVal lnfTreeNew(lClosure* c, lVal v) {
lVal ret = lValAlloc(ltTree);
lTreeRoot *t = ret.vTree = lTreeRootAllocRaw();
for (lVal n = v; n.type == ltPair; n = lCddr(n)) {
lVal car = lCar(n);
if (car.type == ltNil) { break; }
t->root = lTreeInsert(t->root, requireSymbolic(c, car), lCadr(n));
}
return ret;
}
static lVal lnfTreeGetKeys(lClosure* c, lVal v) {
return lTreeKeysToList(requireTree(c, lCar(v))->root);
}
static lVal lnfTreeGetValues(lClosure* c, lVal v) {
return lTreeValuesToList(requireTree(c, lCar(v))->root);
}
static lVal lnfTreeHas(lClosure* c, lVal v) {
return lValBool(lTreeHas(requireTree(c, lCar(v))->root, requireSymbolic(c, lCadr(v)), NULL));
}
static lVal lnfTreeSet(lClosure* c, lVal v) {
lVal car = lCar(v);
if(unlikely(car.type == ltNil)){
car = lValTree(NULL);
}
lTreeRoot* t = requireMutableTree(c, car);
const lSymbol* key = requireSymbolic(c, lCadr(v));
t->root = lTreeInsert(t->root, key, lCaddr(v));
return car;
}
static lVal lnfTreeSize(lClosure* c, lVal v) {
return lValInt(lTreeSize(requireTree(c, lCar(v))->root));
}
static lVal lnfTreeDup(lClosure* c, lVal v) {
(void)c;
if (unlikely((v.type != ltPair)
|| (v.vList->car.type != ltTree))) {
lExceptionThrowValClo("type-error", "tree/dup can only be called with a tree as an argument", v, c);
}
lTree* tree = requireTree(c, lCar(v))->root;
tree = lTreeDup(tree);
return lValTree(tree);
}
static lVal lnfTreeKeyAst(lClosure* c, lVal v) {
lTree* tree = requireTree(c, lCar(v))->root;
return tree ? lValKeywordS(tree->key) : NIL;
}
static lVal lnfTreeValueAst(lClosure* c, lVal v) {
lTree* tree = requireTree(c, lCar(v))->root;
return tree ? tree->value : NIL;
}
static lVal lnfTreeLeftAst(lClosure* c, lVal v) {
lTree* tree = requireTree(c, lCar(v))->root;
return (tree && tree->left) ? lValTree(tree->left) : NIL;
}
static lVal lnfTreeRightAst(lClosure* c, lVal v) {
lTree* tree = requireTree(c, lCar(v))->root;
return (tree && tree->right) ? lValTree(tree->right) : NIL;
}
void lOperationsTree(lClosure* c) {
lAddNativeFunc(c, "tree/new", "plist", "Return a new tree", lnfTreeNew);
lAddNativeFunc(c, "tree/keys", "(tree)", "Return each key of TREE in a list", lnfTreeGetKeys);
lAddNativeFunc(c, "tree/values", "(tree)", "Return each value of TREE in a list", lnfTreeGetValues);
lAddNativeFunc(c, "tree/size", "(tree)", "Return the amount of entries in TREE", lnfTreeSize);
lAddNativeFunc(c, "tree/has?", "(tree sym)", "Return #t if TREE contains a value for SYM", lnfTreeHas);
lAddNativeFunc(c, "tree/set!", "(tree sym val)", "Set SYM to VAL in TREE", lnfTreeSet);
lAddNativeFunc(c, "tree/dup", "(tree)", "Return a duplicate of TREE", lnfTreeDup);
lAddNativeFunc(c, "tree/key*", "(tree)", "Low-level: return the key for TREE segment", lnfTreeKeyAst);
lAddNativeFunc(c, "tree/value*", "(tree)", "Low-level: return the value for TREE segment", lnfTreeValueAst);
lAddNativeFunc(c, "tree/left*", "(tree)", "Low-level: return the left ref for TREE segment", lnfTreeLeftAst);
lAddNativeFunc(c, "tree/right*", "(tree)", "Low-level: return the right ref for TREE segment", lnfTreeRightAst);
}
