#pragma once

#include <stdbool.h>


typedef enum ASTtype{
	AST_LIST,
	AST_WORD,
	AST_NUMBER,
	AST_STRING,
	AST_SYMBOL,
} ASTtype;


typedef struct AST AST;

typedef struct ASTlist{
	int len;
	AST **nodes;
	bool quoted;
} ASTlist;

typedef struct ASTword{
	char *word;
} ASTword;

typedef struct ASTnumber{
	double num;
} ASTnumber;

typedef struct ASTstring{
	char *str;
	int len;
} ASTstring;

typedef struct ASTsymbol{
	char *name;
	int symid;
	//if you're not the interpreter:
	// if you just allocated the ASTsymbol yourself, set symid to -1;
	// else, leave symid alone.
	//You should probably use ast_symbol(), in which case you don't have to do anything.
} ASTsymbol;

struct AST{
	ASTtype type;
	union {
		ASTlist l;
		ASTword w;
		ASTnumber n;
		ASTstring S;
		ASTsymbol s;
	};
};


void ast_free(AST *ast);

AST* ast_copy(const AST *ast);

char* ast_stringify(const AST *ast);

AST* ast_list(int len,AST **nodes); //these convenience functions DO NOT copy their arguments
AST* ast_word(char *word);
AST* ast_number(double num);
AST* ast_string(char *str,int len);
AST* ast_symbol(char *name);