initial commit

projects/task3/thm_apply.c

@@ -0,0 +1,67 @@
+#include "ast.h"
+
+term* sub_thm(term* thm, var_sub_list* list){
+    if(list == (void*) 0) return copy_term(thm);
+    if(thm->type == Quant){
+        term* den = list->cur->sub_term;
+        return sub_thm(subst_term(den, list->cur->var, thm->content.Quant.body), list->next);
+    }
+    else return (void*) 0;
+}
+
+// apply (apply (impl) h1) (h2)
+//不是imply形式时返回(void*) 0
+ImplyProp *separate_imply(term *t)
+{
+    if (t->type != Apply || t->content.Apply.left->type != Apply ||
+        t->content.Apply.left->content.Apply.left->type != Const ||
+        t->content.Apply.left->content.Apply.left->content.Const.type != Impl)
+        return (void*) 0;
+    else
+        return createImplyProp(t->content.Apply.left->content.Apply.right, t->content.Apply.right);
+}
+
+//根据定理形式，匹配结论，得出要检验的前提
+term_list* check_list_gen(term* thm, term* target) {
+    if (thm == (void*) 0 || target == (void*) 0) {
+        return (void*) 0;
+    }
+    term_list* check_list = (void*) 0;
+    term_list** tail_ptr = &check_list; 
+    while (thm != (void*) 0 && !alpha_equiv(thm, target)) {
+        ImplyProp* p = separate_imply(thm);    
+        if (p == (void*) 0) {
+            free_term_list(check_list);
+            return (void*) 0;
+        }
+        // 添加新节点到链表
+        term_list* new_node = malloc_term_list();        
+        new_node->element = p->assum;  // 转移所有权
+        new_node->next = (void*) 0;
+        
+        *tail_ptr = new_node;
+        tail_ptr = &(new_node->next);     
+        thm = p->concl;     
+        free_imply_prop(p); // 释放ImplyProp结构体（不释放其成员）
+    }
+    return check_list;
+}
+
+
+solve_res* thm_apply(term* thm, var_sub_list* list, term* goal){
+    term* thm_ins = sub_thm(thm, list);
+    solve_res* res = malloc_solve_res();
+    if(thm_ins == (void*) 0) {
+        res->type = bool_res;
+        res->d.ans = false;
+    }
+    else if(alpha_equiv(thm_ins, goal)){
+        res->type = bool_res;
+        res->d.ans = true;
+    }
+    else{
+        res->type = termlist;
+        res->d.list = check_list_gen(thm_ins, goal);
+    }
+    return res;
+}