eval.c

#include "eval.h"
#include "lexer.h"

Decimal evaluate(TreeNode *tn) {
    if (!tn) return 0.0f;

    switch (tn->token.type) {
        case BEGIN:
            return evaluate(tn->left);
            break;
        case ADD:
            return evaluate(tn->left) + evaluate(tn->right);
            break;
        case MIN:
            return evaluate(tn->left) - evaluate(tn->right);
            break;
        case MUL:
            return evaluate(tn->left) * evaluate(tn->right);
            break;
        case DIV:
            return evaluate(tn->left) / evaluate(tn->right);
            break;
        case MOD:
            {
                int l = evaluate(tn->left);
                int r = evaluate(tn->right);
                return l % r;
            }
            break;
        case EQ:
            return evaluate(tn->left) == evaluate(tn->right);
            break;
        case NE:
            return evaluate(tn->left) != evaluate(tn->right);
            break;
        case LT:
            return evaluate(tn->left) < evaluate(tn->right);
            break;
        case LE:
            return evaluate(tn->left) <= evaluate(tn->right);
            break;
        case GT:
            return evaluate(tn->left) > evaluate(tn->right);
            break;
        case GE:
            return evaluate(tn->left) >= evaluate(tn->right);
            break;
        case AND:
            return evaluate(tn->left) && evaluate(tn->right);
            break;
        case OR:
            return evaluate(tn->left) || evaluate(tn->right);
            break;
        case NUMBER:
            return tn->token.number;
            break;
        case DECIMAL:
            return tn->token.decimal;
            break;
        case PAREN:
            return evaluate(tn->left);
        default:
            return 0.0f;
            break;
    }
}