Files
Toy/source/toy_parser.c
Kayne Ruse cc4ff3f6d8 Fixed logical AND and OR operators, read more
The definition of '&&':
  Return the first falsy value, or the last value, skipping the evaluation of other operands.

The definition of '||':
  Return the first truthy value, or the last value, skipping the evaluation of other operands.

Toy now follows these definitions.

Fixed #154
2024-12-26 16:09:16 +11:00

998 lines
32 KiB
C

#include "toy_parser.h"
#include "toy_console_colors.h"
#include "toy_value.h"
#include "toy_string.h"
#include <stdio.h>
//utilities
static void printError(Toy_Parser* parser, Toy_Token token, const char* errorMsg) {
//keep going while panicking
if (parser->panic) {
return;
}
fprintf(stderr, TOY_CC_ERROR "[Line %d] Error ", (int)token.line);
//check type
if (token.type == TOY_TOKEN_EOF) {
fprintf(stderr, "at end");
}
else {
fprintf(stderr, "at '%.*s'", (int)token.length, token.lexeme);
}
//finally
fprintf(stderr, ": %s\n" TOY_CC_RESET, errorMsg);
parser->error = true;
parser->panic = true;
}
static void advance(Toy_Parser* parser) {
parser->previous = parser->current;
parser->current = Toy_private_scanLexer(parser->lexer);
if (parser->current.type == TOY_TOKEN_ERROR) {
printError(parser, parser->current, "Can't read the source code");
}
}
static bool match(Toy_Parser* parser, Toy_TokenType tokenType) {
if (parser->current.type == tokenType) {
advance(parser);
return true;
}
return false;
}
static void consume(Toy_Parser* parser, Toy_TokenType tokenType, const char* msg) {
if (parser->current.type != tokenType) {
printError(parser, parser->current, msg);
return;
}
advance(parser);
}
static void synchronize(Toy_Parser* parser) {
while (parser->current.type != TOY_TOKEN_EOF) {
switch(parser->current.type) {
//these tokens can start a statement
case TOY_TOKEN_KEYWORD_ASSERT:
case TOY_TOKEN_KEYWORD_BREAK:
case TOY_TOKEN_KEYWORD_CLASS:
case TOY_TOKEN_KEYWORD_CONTINUE:
case TOY_TOKEN_KEYWORD_DO:
case TOY_TOKEN_KEYWORD_EXPORT:
case TOY_TOKEN_KEYWORD_FOR:
case TOY_TOKEN_KEYWORD_FOREACH:
case TOY_TOKEN_KEYWORD_FUNCTION:
case TOY_TOKEN_KEYWORD_IF:
case TOY_TOKEN_KEYWORD_IMPORT:
case TOY_TOKEN_KEYWORD_PRINT:
case TOY_TOKEN_KEYWORD_RETURN:
case TOY_TOKEN_KEYWORD_VAR:
case TOY_TOKEN_KEYWORD_WHILE:
case TOY_TOKEN_KEYWORD_YIELD:
parser->error = true;
parser->panic = false;
return;
default:
advance(parser);
}
}
}
//precedence declarations
typedef enum ParsingPrecedence {
PREC_NONE,
PREC_ASSIGNMENT,
PREC_GROUP,
PREC_TERNARY,
PREC_NEGATE,
PREC_OR,
PREC_AND,
PREC_COMPARISON,
PREC_TERM,
PREC_FACTOR,
PREC_UNARY,
PREC_CALL,
PREC_PRIMARY,
} ParsingPrecedence;
typedef Toy_AstFlag (*ParsingRule)(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
typedef struct ParsingTuple {
ParsingPrecedence precedence;
ParsingRule prefix;
ParsingRule infix;
} ParsingTuple;
static void parsePrecedence(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle, ParsingPrecedence precRule);
static Toy_AstFlag nameString(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static Toy_AstFlag literal(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static Toy_AstFlag unary(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static Toy_AstFlag binary(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static Toy_AstFlag group(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static Toy_AstFlag compound(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static Toy_AstFlag aggregate(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
//precedence definitions
static ParsingTuple parsingRulesetTable[] = {
{PREC_PRIMARY,literal,NULL},// TOY_TOKEN_NULL,
//variable names (initially handled as a string)
{PREC_PRIMARY,nameString,NULL},// TOY_TOKEN_NAME,
//types
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_BOOLEAN,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_INTEGER,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_FLOAT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_STRING,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_ARRAY,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_TABLE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_FUNCTION,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_OPAQUE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_TYPE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_TYPE_ANY,
//keywords and reserved words
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_AS,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_ASSERT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_BREAK,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_CLASS,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_CONST,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_CONTINUE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_DO,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_ELSE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_EXPORT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_FOR,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_FOREACH,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_FUNCTION,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_IF,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_IMPORT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_IN,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_OF,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_PRINT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_RETURN,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_TYPEAS,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_TYPEOF,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_VAR,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_WHILE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_KEYWORD_YIELD,
//literal values
{PREC_PRIMARY,literal,NULL},// TOY_TOKEN_LITERAL_TRUE,
{PREC_PRIMARY,literal,NULL},// TOY_TOKEN_LITERAL_FALSE,
{PREC_PRIMARY,literal,NULL},// TOY_TOKEN_LITERAL_INTEGER,
{PREC_PRIMARY,literal,NULL},// TOY_TOKEN_LITERAL_FLOAT,
{PREC_PRIMARY,literal,NULL},// TOY_TOKEN_LITERAL_STRING,
//math operators
{PREC_TERM,NULL,binary},// TOY_TOKEN_OPERATOR_ADD,
{PREC_TERM,unary,binary},// TOY_TOKEN_OPERATOR_SUBTRACT,
{PREC_FACTOR,NULL,binary},// TOY_TOKEN_OPERATOR_MULTIPLY,
{PREC_FACTOR,NULL,binary},// TOY_TOKEN_OPERATOR_DIVIDE,
{PREC_FACTOR,NULL,binary},// TOY_TOKEN_OPERATOR_MODULO,
{PREC_ASSIGNMENT,NULL,binary},// TOY_TOKEN_OPERATOR_ADD_ASSIGN,
{PREC_ASSIGNMENT,NULL,binary},// TOY_TOKEN_OPERATOR_SUBTRACT_ASSIGN,
{PREC_ASSIGNMENT,NULL,binary},// TOY_TOKEN_OPERATOR_MULTIPLY_ASSIGN,
{PREC_ASSIGNMENT,NULL,binary},// TOY_TOKEN_OPERATOR_DIVIDE_ASSIGN,
{PREC_ASSIGNMENT,NULL,binary},// TOY_TOKEN_OPERATOR_MODULO_ASSIGN,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_INCREMENT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_DECREMENT,
{PREC_ASSIGNMENT,NULL,binary},// TOY_TOKEN_OPERATOR_ASSIGN,
//comparator operators
{PREC_COMPARISON,NULL,binary},// TOY_TOKEN_OPERATOR_COMPARE_EQUAL,
{PREC_COMPARISON,NULL,binary},// TOY_TOKEN_OPERATOR_COMPARE_NOT,
{PREC_COMPARISON,NULL,binary},// TOY_TOKEN_OPERATOR_COMPARE_LESS,
{PREC_COMPARISON,NULL,binary},// TOY_TOKEN_OPERATOR_COMPARE_LESS_EQUAL,
{PREC_COMPARISON,NULL,binary},// TOY_TOKEN_OPERATOR_COMPARE_GREATER,
{PREC_COMPARISON,NULL,binary},// TOY_TOKEN_OPERATOR_COMPARE_GREATER_EQUAL,
//structural operators
{PREC_GROUP,group,NULL},// TOY_TOKEN_OPERATOR_PAREN_LEFT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_PAREN_RIGHT,
{PREC_GROUP,compound,aggregate},// TOY_TOKEN_OPERATOR_BRACKET_LEFT,
{PREC_NONE,compound,aggregate},// TOY_TOKEN_OPERATOR_BRACKET_RIGHT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_BRACE_LEFT,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_BRACE_RIGHT,
//other operators
{PREC_AND,NULL,binary},// TOY_TOKEN_OPERATOR_AND,
{PREC_OR,NULL,binary},// TOY_TOKEN_OPERATOR_OR,
{PREC_NEGATE,unary,NULL},// TOY_TOKEN_OPERATOR_NEGATE,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_QUESTION,
{PREC_GROUP,compound,aggregate},// TOY_TOKEN_OPERATOR_COLON,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_SEMICOLON, // ;
{PREC_GROUP,NULL,aggregate},// TOY_TOKEN_OPERATOR_COMMA, // ,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_DOT, // .
{PREC_CALL,NULL,binary},// TOY_TOKEN_OPERATOR_CONCAT, // ..
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_REST, // ...
//unused operators
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_AMPERSAND, // &
{PREC_NONE,NULL,NULL},// TOY_TOKEN_OPERATOR_PIPE, // |
//meta tokens
{PREC_NONE,NULL,NULL},// TOY_TOKEN_PASS,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_ERROR,
{PREC_NONE,NULL,NULL},// TOY_TOKEN_EOF,
};
static Toy_ValueType readType(Toy_Parser* parser) {
advance(parser);
switch(parser->previous.type) {
case TOY_TOKEN_TYPE_BOOLEAN:
return TOY_VALUE_BOOLEAN;
case TOY_TOKEN_TYPE_INTEGER:
return TOY_VALUE_INTEGER;
case TOY_TOKEN_TYPE_FLOAT:
return TOY_VALUE_FLOAT;
case TOY_TOKEN_TYPE_STRING:
return TOY_VALUE_STRING;
case TOY_TOKEN_TYPE_ARRAY:
return TOY_VALUE_ARRAY;
case TOY_TOKEN_TYPE_TABLE:
return TOY_VALUE_TABLE;
case TOY_TOKEN_TYPE_FUNCTION:
return TOY_VALUE_FUNCTION;
case TOY_TOKEN_TYPE_OPAQUE:
return TOY_VALUE_OPAQUE;
case TOY_TOKEN_TYPE_TYPE:
return TOY_VALUE_TYPE;
case TOY_TOKEN_TYPE_ANY:
return TOY_VALUE_ANY;
default:
printError(parser, parser->previous, "Expected type identifier");
return TOY_VALUE_UNKNOWN;
}
}
static Toy_AstFlag nameString(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//emit the name string
Toy_String* name = Toy_createNameStringLength(bucketHandle, parser->previous.lexeme, parser->previous.length, TOY_VALUE_UNKNOWN, false);
Toy_Value value = TOY_VALUE_FROM_STRING(name);
Toy_private_emitAstValue(bucketHandle, rootHandle, value);
//check for an assignment
Toy_AstFlag flag = TOY_AST_FLAG_NONE;
if (match(parser, TOY_TOKEN_OPERATOR_ASSIGN)) {
flag = TOY_AST_FLAG_ASSIGN;
}
else if (match(parser, TOY_TOKEN_OPERATOR_ADD_ASSIGN)) {
flag = TOY_AST_FLAG_ADD_ASSIGN;
}
else if (match(parser, TOY_TOKEN_OPERATOR_SUBTRACT_ASSIGN)) {
flag = TOY_AST_FLAG_SUBTRACT_ASSIGN;
}
else if (match(parser, TOY_TOKEN_OPERATOR_MULTIPLY_ASSIGN)) {
flag = TOY_AST_FLAG_MULTIPLY_ASSIGN;
}
else if (match(parser, TOY_TOKEN_OPERATOR_DIVIDE_ASSIGN)) {
flag = TOY_AST_FLAG_DIVIDE_ASSIGN;
}
else if (match(parser, TOY_TOKEN_OPERATOR_MODULO_ASSIGN)) {
flag = TOY_AST_FLAG_MODULO_ASSIGN;
}
//emit the assignment if found
if (flag != TOY_AST_FLAG_NONE) {
Toy_Ast* expr = NULL;
parsePrecedence(bucketHandle, parser, &expr, PREC_ASSIGNMENT); //this makes chained assignment possible, I think
Toy_private_emitAstVariableAssignment(bucketHandle, rootHandle, flag, expr);
return TOY_AST_FLAG_NONE;
}
//assume it's an access instead
Toy_private_emitAstVariableAccess(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
static Toy_AstFlag literal(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
switch(parser->previous.type) {
case TOY_TOKEN_NULL:
Toy_private_emitAstValue(bucketHandle, rootHandle, TOY_VALUE_FROM_NULL());
return TOY_AST_FLAG_NONE;
case TOY_TOKEN_LITERAL_TRUE:
Toy_private_emitAstValue(bucketHandle, rootHandle, TOY_VALUE_FROM_BOOLEAN(true));
return TOY_AST_FLAG_NONE;
case TOY_TOKEN_LITERAL_FALSE:
Toy_private_emitAstValue(bucketHandle, rootHandle, TOY_VALUE_FROM_BOOLEAN(false));
return TOY_AST_FLAG_NONE;
case TOY_TOKEN_LITERAL_INTEGER: {
//filter the '_' character
char buffer[parser->previous.length];
unsigned int i = 0, o = 0;
do {
buffer[i] = parser->previous.lexeme[o];
if (buffer[i] != '_') i++;
} while (parser->previous.lexeme[o++] && i < parser->previous.length);
buffer[i] = '\0'; //BUGFIX
int value = 0;
sscanf(buffer, "%d", &value);
Toy_private_emitAstValue(bucketHandle, rootHandle, TOY_VALUE_FROM_INTEGER(value));
return TOY_AST_FLAG_NONE;
}
case TOY_TOKEN_LITERAL_FLOAT: {
//filter the '_' character
char buffer[parser->previous.length];
unsigned int i = 0, o = 0;
do {
buffer[i] = parser->previous.lexeme[o];
if (buffer[i] != '_') i++;
} while (parser->previous.lexeme[o++] && i < parser->previous.length);
buffer[i] = '\0'; //BUGFIX
float value = 0;
sscanf(buffer, "%f", &value);
Toy_private_emitAstValue(bucketHandle, rootHandle, TOY_VALUE_FROM_FLOAT(value));
return TOY_AST_FLAG_NONE;
}
case TOY_TOKEN_LITERAL_STRING: {
char buffer[parser->previous.length + 1];
unsigned int escapeCounter = 0;
unsigned int i = 0, o = 0;
if (parser->previous.length > 0) { //BUGFIX: compensate for zero-length strings
do {
buffer[i] = parser->previous.lexeme[o];
if (buffer[i] == '\\' && parser->previous.lexeme[++o]) {
escapeCounter++;
//also handle escape characters
switch(parser->previous.lexeme[o]) {
case 'n':
buffer[i] = '\n';
break;
case 't':
buffer[i] = '\t';
break;
case '\\':
buffer[i] = '\\';
break;
case '"':
buffer[i] = '"';
break;
}
}
i++;
} while (parser->previous.lexeme[o++] && i < parser->previous.length);
}
buffer[i] = '\0';
unsigned int len = i - escapeCounter; //NOTE: len is ONLY the string length
Toy_private_emitAstValue(bucketHandle, rootHandle, TOY_VALUE_FROM_STRING(Toy_createStringLength(bucketHandle, buffer, len)));
return TOY_AST_FLAG_NONE;
}
default:
printError(parser, parser->previous, "Unexpected token passed to literal precedence rule");
Toy_private_emitAstError(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
}
static Toy_AstFlag unary(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//'subtract' can only be applied to numbers and groups, while 'negate' can only be applied to booleans and groups
if (parser->previous.type == TOY_TOKEN_OPERATOR_SUBTRACT) {
bool connectedDigit = parser->previous.lexeme[1] >= '0' && parser->previous.lexeme[1] <= '9'; //BUGFIX: '- 1' should not be optimised into a negative
parsePrecedence(bucketHandle, parser, rootHandle, PREC_UNARY);
//negative numbers
if ((*rootHandle)->type == TOY_AST_VALUE && TOY_VALUE_IS_INTEGER((*rootHandle)->value.value) && connectedDigit) {
(*rootHandle)->value.value = TOY_VALUE_FROM_INTEGER( -TOY_VALUE_AS_INTEGER((*rootHandle)->value.value) );
}
else if ((*rootHandle)->type == TOY_AST_VALUE && TOY_VALUE_IS_FLOAT((*rootHandle)->value.value) && connectedDigit) {
(*rootHandle)->value.value = TOY_VALUE_FROM_FLOAT( -TOY_VALUE_AS_FLOAT((*rootHandle)->value.value) );
}
else {
//actually emit the negation node
Toy_private_emitAstUnary(bucketHandle, rootHandle, TOY_AST_FLAG_NEGATE);
}
}
else if (parser->previous.type == TOY_TOKEN_OPERATOR_NEGATE) {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_UNARY);
Toy_private_emitAstUnary(bucketHandle, rootHandle, TOY_AST_FLAG_NEGATE);
}
else {
printError(parser, parser->previous, "Unexpected token passed to unary precedence rule");
Toy_private_emitAstError(bucketHandle, rootHandle);
}
return TOY_AST_FLAG_NONE;
}
static Toy_AstFlag binary(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//infix must advance
advance(parser);
switch(parser->previous.type) {
//arithmetic
case TOY_TOKEN_OPERATOR_ADD: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_TERM + 1);
return TOY_AST_FLAG_ADD;
}
case TOY_TOKEN_OPERATOR_SUBTRACT: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_TERM + 1);
return TOY_AST_FLAG_SUBTRACT;
}
case TOY_TOKEN_OPERATOR_MULTIPLY: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_FACTOR + 1);
return TOY_AST_FLAG_MULTIPLY;
}
case TOY_TOKEN_OPERATOR_DIVIDE: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_FACTOR + 1);
return TOY_AST_FLAG_DIVIDE;
}
case TOY_TOKEN_OPERATOR_MODULO: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_FACTOR + 1);
return TOY_AST_FLAG_MODULO;
}
//assignment
case TOY_TOKEN_OPERATOR_ASSIGN: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT + 1);
return TOY_AST_FLAG_ASSIGN;
}
case TOY_TOKEN_OPERATOR_ADD_ASSIGN: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT + 1);
return TOY_AST_FLAG_ADD_ASSIGN;
}
case TOY_TOKEN_OPERATOR_SUBTRACT_ASSIGN: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT + 1);
return TOY_AST_FLAG_SUBTRACT_ASSIGN;
}
case TOY_TOKEN_OPERATOR_MULTIPLY_ASSIGN: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT + 1);
return TOY_AST_FLAG_MULTIPLY_ASSIGN;
}
case TOY_TOKEN_OPERATOR_DIVIDE_ASSIGN: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT + 1);
return TOY_AST_FLAG_DIVIDE_ASSIGN;
}
case TOY_TOKEN_OPERATOR_MODULO_ASSIGN: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT + 1);
return TOY_AST_FLAG_MODULO_ASSIGN;
}
//comparison
case TOY_TOKEN_OPERATOR_COMPARE_EQUAL: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_COMPARISON + 1);
return TOY_AST_FLAG_COMPARE_EQUAL;
}
case TOY_TOKEN_OPERATOR_COMPARE_NOT: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_COMPARISON + 1);
return TOY_AST_FLAG_COMPARE_NOT;
}
case TOY_TOKEN_OPERATOR_COMPARE_LESS: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_COMPARISON + 1);
return TOY_AST_FLAG_COMPARE_LESS;
}
case TOY_TOKEN_OPERATOR_COMPARE_LESS_EQUAL: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_COMPARISON + 1);
return TOY_AST_FLAG_COMPARE_LESS_EQUAL;
}
case TOY_TOKEN_OPERATOR_COMPARE_GREATER: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_COMPARISON + 1);
return TOY_AST_FLAG_COMPARE_GREATER;
}
case TOY_TOKEN_OPERATOR_COMPARE_GREATER_EQUAL: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_COMPARISON + 1);
return TOY_AST_FLAG_COMPARE_GREATER_EQUAL;
}
//logical
case TOY_TOKEN_OPERATOR_AND: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_AND + 1);
return TOY_AST_FLAG_AND;
}
case TOY_TOKEN_OPERATOR_OR: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_OR + 1);
return TOY_AST_FLAG_OR;
}
case TOY_TOKEN_OPERATOR_CONCAT: {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_CALL + 1);
return TOY_AST_FLAG_CONCAT;
}
default:
printError(parser, parser->previous, "Unexpected token passed to binary precedence rule");
Toy_private_emitAstError(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
}
static Toy_AstFlag group(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//groups are ()
if (parser->previous.type == TOY_TOKEN_OPERATOR_PAREN_LEFT) {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_GROUP);
consume(parser, TOY_TOKEN_OPERATOR_PAREN_RIGHT, "Expected ')' at end of group");
//Toy_AstGroup could be omitted, but is kept for now
Toy_private_emitAstGroup(bucketHandle, rootHandle);
}
else {
printError(parser, parser->previous, "Unexpected token passed to grouping precedence rule");
Toy_private_emitAstError(bucketHandle, rootHandle);
}
return TOY_AST_FLAG_NONE;
}
static Toy_AstFlag compound(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//read in an array or table compound definition
if (parser->previous.type == TOY_TOKEN_OPERATOR_BRACKET_LEFT) {
//BUGFIX: special case for empty arrays
if (match(parser, TOY_TOKEN_OPERATOR_BRACKET_RIGHT)) {
Toy_private_emitAstPass(bucketHandle, rootHandle);
Toy_private_emitAstCompound(bucketHandle, rootHandle, TOY_AST_FLAG_COMPOUND_ARRAY);
return TOY_AST_FLAG_NONE;
}
//BUGFIX: special case for empty tables
if (match(parser, TOY_TOKEN_OPERATOR_COLON)) {
consume(parser, TOY_TOKEN_OPERATOR_BRACKET_RIGHT, "Expected ']' at the end of empty table");
Toy_private_emitAstPass(bucketHandle, rootHandle);
Toy_private_emitAstAggregate(bucketHandle, rootHandle, TOY_AST_FLAG_PAIR, *rootHandle);
Toy_private_emitAstCompound(bucketHandle, rootHandle, TOY_AST_FLAG_COMPOUND_TABLE);
return TOY_AST_FLAG_NONE;
}
parsePrecedence(bucketHandle, parser, rootHandle, PREC_GROUP);
//peek inside to see what you have
Toy_AstFlag flag = TOY_AST_FLAG_NONE;
if ((*rootHandle)->type == TOY_AST_AGGREGATE) {
//1 element in a table will mean the top-level node is a collection
flag = (*rootHandle)->aggregate.flag;
//more than 1 element in a table will mean you need to check the last element in the collection to find a pair
if (flag == TOY_AST_FLAG_COLLECTION && (*rootHandle)->aggregate.right->type == TOY_AST_AGGREGATE) {
flag = (*rootHandle)->aggregate.right->aggregate.flag; //yes, this is hacky
}
}
//BUGFIX: special case for trailing commas
if (parser->previous.type == TOY_TOKEN_OPERATOR_BRACKET_RIGHT && parser->current.type != TOY_TOKEN_OPERATOR_BRACKET_RIGHT) {
Toy_private_emitAstCompound(bucketHandle, rootHandle, flag == TOY_AST_FLAG_PAIR ? TOY_AST_FLAG_COMPOUND_TABLE : TOY_AST_FLAG_COMPOUND_ARRAY);
return TOY_AST_FLAG_NONE;
}
consume(parser, TOY_TOKEN_OPERATOR_BRACKET_RIGHT, "Expected ']' at the end of compound expression");
Toy_private_emitAstCompound(bucketHandle, rootHandle, flag == TOY_AST_FLAG_PAIR ? TOY_AST_FLAG_COMPOUND_TABLE : TOY_AST_FLAG_COMPOUND_ARRAY);
return TOY_AST_FLAG_NONE;
}
else if (parser->previous.type == TOY_TOKEN_OPERATOR_BRACKET_RIGHT) {
//allows for trailing commas
Toy_private_emitAstPass(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
else {
printError(parser, parser->previous, "Unexpected token passed to compound precedence rule");
Toy_private_emitAstError(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
}
static Toy_AstFlag aggregate(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//infix must advance
advance(parser);
//aggregates are a collection of parts, expressing a larger idea
if (parser->previous.type == TOY_TOKEN_OPERATOR_COMMA) {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_GROUP); //NOT +1, as compounds are right-recursive
return TOY_AST_FLAG_COLLECTION;
}
if (parser->previous.type == TOY_TOKEN_OPERATOR_COLON) {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_GROUP); //NOT +1, as compounds are right-recursive
return TOY_AST_FLAG_PAIR;
}
else if (parser->previous.type == TOY_TOKEN_OPERATOR_BRACKET_LEFT) {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_GROUP);
consume(parser, TOY_TOKEN_OPERATOR_BRACKET_RIGHT, "Expected ']' at the end of index expression");
return TOY_AST_FLAG_INDEX;
}
else if (parser->previous.type == TOY_TOKEN_OPERATOR_BRACKET_RIGHT) {
Toy_private_emitAstPass(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
else {
printError(parser, parser->previous, "Unexpected token passed to aggregate precedence rule");
Toy_private_emitAstError(bucketHandle, rootHandle);
return TOY_AST_FLAG_NONE;
}
}
static ParsingTuple* getParsingRule(Toy_TokenType type) {
return &parsingRulesetTable[type];
}
//grammar rules
static void parsePrecedence(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle, ParsingPrecedence precRule) {
//'step over' the token to parse
advance(parser);
//every valid expression has a prefix rule
ParsingRule prefix = getParsingRule(parser->previous.type)->prefix;
if (prefix == NULL) {
//make a nice error message
if (Toy_private_findKeywordByType(parser->previous.type)) {
printError(parser, parser->previous, "Found reserved keyword instead");
}
else {
printError(parser, parser->previous, "Expected expression");
}
Toy_private_emitAstError(bucketHandle, rootHandle);
return;
}
prefix(bucketHandle, parser, rootHandle);
//infix rules are left-recursive
while (precRule <= getParsingRule(parser->current.type)->precedence) {
ParsingRule infix = getParsingRule(parser->current.type)->infix;
if (infix == NULL) {
printError(parser, parser->previous, "Expected operator");
Toy_private_emitAstError(bucketHandle, rootHandle);
return;
}
Toy_Ast* ptr = NULL;
Toy_AstFlag flag = infix(bucketHandle, parser, &ptr);
//finished
if (flag == TOY_AST_FLAG_NONE) {
(*rootHandle) = ptr;
return;
}
//eww, gross
else if (flag >= 10 && flag <= 19) {
Toy_private_emitAstVariableAssignment(bucketHandle, rootHandle, flag, ptr);
}
else if (flag >= 20 && flag <= 29) {
Toy_private_emitAstCompare(bucketHandle, rootHandle, flag, ptr);
}
else if (flag >= 30 && flag <= 39) {
Toy_private_emitAstAggregate(bucketHandle, rootHandle, flag, ptr);
}
else {
//BUGFIX: '&&' and '||' are special cases, with short-circuit logic
if (flag == TOY_AST_FLAG_AND || flag == TOY_AST_FLAG_OR) {
Toy_private_emitAstBinaryShortCircuit(bucketHandle, rootHandle, flag, ptr);
}
else {
Toy_private_emitAstBinary(bucketHandle, rootHandle, flag, ptr);
}
}
}
//can't assign below a certain precedence
if (precRule <= PREC_ASSIGNMENT && match(parser, TOY_TOKEN_OPERATOR_ASSIGN)) {
printError(parser, parser->current, "Invalid assignment target");
}
}
static void makeExpr(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
parsePrecedence(bucketHandle, parser, rootHandle, PREC_ASSIGNMENT);
}
//forward declarations
static void makeBlockStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static void makeDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle);
static void makeAssertStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
Toy_Ast* ast = NULL; //assert's emit function is a bit different
makeExpr(bucketHandle, parser, &ast);
//if assert is disabled, don't emit the assert
if (parser->removeAssert) {
Toy_private_emitAstPass(bucketHandle, rootHandle);
}
else {
//NOTE: if it's an aggregate node, then it's got a second arg
if (ast->type == TOY_AST_AGGREGATE) {
Toy_private_emitAstAssert(bucketHandle, rootHandle, ast->aggregate.left, ast->aggregate.right);
}
else {
Toy_private_emitAstAssert(bucketHandle, rootHandle, ast, NULL);
}
}
consume(parser, TOY_TOKEN_OPERATOR_SEMICOLON, "Expected ';' at the end of assert statement");
}
static void makeIfThenElseStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
Toy_Ast* condBranch = NULL;
Toy_Ast* thenBranch = NULL;
Toy_Ast* elseBranch = NULL;
//if (condBranch)
consume(parser, TOY_TOKEN_OPERATOR_PAREN_LEFT, "Expected '(' after 'if' keyword");
makeExpr(bucketHandle, parser, &condBranch);
consume(parser, TOY_TOKEN_OPERATOR_PAREN_RIGHT, "Expected ')' after 'if' condition");
// { thenBranch }
makeDeclarationStmt(bucketHandle, parser, &thenBranch);
//else { elseBranch }
if (match(parser, TOY_TOKEN_KEYWORD_ELSE)) {
makeDeclarationStmt(bucketHandle, parser, &elseBranch);
}
Toy_private_emitAstIfThenElse(bucketHandle, rootHandle, condBranch, thenBranch, elseBranch);
}
static void makeWhileStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
Toy_Ast* condBranch = NULL;
Toy_Ast* thenBranch = NULL;
//while (condBranch)
consume(parser, TOY_TOKEN_OPERATOR_PAREN_LEFT, "Expected '(' after 'while' keyword");
makeExpr(bucketHandle, parser, &condBranch);
consume(parser, TOY_TOKEN_OPERATOR_PAREN_RIGHT, "Expected ')' after 'while' condition");
// { thenBranch }
makeDeclarationStmt(bucketHandle, parser, &thenBranch);
Toy_private_emitAstWhileThen(bucketHandle, rootHandle, condBranch, thenBranch);
}
static void makeBreakStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
Toy_private_emitAstBreak(bucketHandle, rootHandle);
consume(parser, TOY_TOKEN_OPERATOR_SEMICOLON, "Expected ';' at the end of break statement");
}
static void makeContinueStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
Toy_private_emitAstContinue(bucketHandle, rootHandle);
consume(parser, TOY_TOKEN_OPERATOR_SEMICOLON, "Expected ';' at the end of continue statement");
}
static void makePrintStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
makeExpr(bucketHandle, parser, rootHandle);
Toy_private_emitAstPrint(bucketHandle, rootHandle);
consume(parser, TOY_TOKEN_OPERATOR_SEMICOLON, "Expected ';' at the end of print statement");
}
static void makeExprStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
makeExpr(bucketHandle, parser, rootHandle);
consume(parser, TOY_TOKEN_OPERATOR_SEMICOLON, "Expected ';' at the end of expression statement");
}
static void makeVariableDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
consume(parser, TOY_TOKEN_NAME, "Expected variable name after 'var' keyword");
if (parser->previous.length > 255) {
printError(parser, parser->previous, "Can't have a variable name longer than 255 characters");
Toy_private_emitAstError(bucketHandle, rootHandle);
return;
}
Toy_Token nameToken = parser->previous;
//read the type specifier if present
Toy_ValueType varType = TOY_VALUE_ANY;
bool constant = false;
if (match(parser, TOY_TOKEN_OPERATOR_COLON)) {
varType = readType(parser);
if (match(parser, TOY_TOKEN_KEYWORD_CONST)) {
constant = true;
}
}
//build the string
Toy_String* nameStr = Toy_createNameStringLength(bucketHandle, nameToken.lexeme, nameToken.length, varType, constant);
//if there's an assignment, read it, or default to null
Toy_Ast* expr = NULL;
if (match(parser, TOY_TOKEN_OPERATOR_ASSIGN)) {
makeExpr(bucketHandle, parser, &expr);
}
else {
Toy_private_emitAstValue(bucketHandle, &expr, TOY_VALUE_FROM_NULL());
}
//finally, emit the declaration as an Ast
Toy_private_emitAstVariableDeclaration(bucketHandle, rootHandle, nameStr, expr);
}
static void makeStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//inner scope
if (match(parser, TOY_TOKEN_OPERATOR_BRACE_LEFT)) {
makeBlockStmt(bucketHandle, parser, rootHandle);
consume(parser, TOY_TOKEN_OPERATOR_BRACE_RIGHT, "Expected '}' at the end of block scope");
(*rootHandle)->block.innerScope = true;
return;
}
//assert
else if (match(parser, TOY_TOKEN_KEYWORD_ASSERT)) {
makeAssertStmt(bucketHandle, parser, rootHandle);
return;
}
//if-then-else
else if (match(parser, TOY_TOKEN_KEYWORD_IF)) {
makeIfThenElseStmt(bucketHandle, parser, rootHandle);
return;
}
//while-then
else if (match(parser, TOY_TOKEN_KEYWORD_WHILE)) {
makeWhileStmt(bucketHandle, parser, rootHandle);
return;
}
//for-pre-clause-post-then
//return
//import
//break
else if (match(parser, TOY_TOKEN_KEYWORD_BREAK)) {
makeBreakStmt(bucketHandle, parser, rootHandle);
return;
}
//continue
else if (match(parser, TOY_TOKEN_KEYWORD_CONTINUE)) {
makeContinueStmt(bucketHandle, parser, rootHandle);
return;
}
//print
else if (match(parser, TOY_TOKEN_KEYWORD_PRINT)) {
makePrintStmt(bucketHandle, parser, rootHandle);
return;
}
//empty lines
else if (match(parser, TOY_TOKEN_OPERATOR_SEMICOLON)) {
Toy_private_emitAstPass(bucketHandle, rootHandle);
return;
}
//expressions
else {
//default
makeExprStmt(bucketHandle, parser, rootHandle);
return;
}
}
static void makeDeclarationStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//variable declarations
if (match(parser, TOY_TOKEN_KEYWORD_VAR)) {
makeVariableDeclarationStmt(bucketHandle, parser, rootHandle);
}
// //function declarations
// else if (match(parser, TOY_TOKEN_KEYWORD_FUNCTION)) {
// makeFunctionDeclarationStmt(bucketHandle, parser, rootHandle);
// }
//otherwise
else {
makeStmt(bucketHandle, parser, rootHandle);
}
}
static void makeBlockStmt(Toy_Bucket** bucketHandle, Toy_Parser* parser, Toy_Ast** rootHandle) {
//begin the block
Toy_private_initAstBlock(bucketHandle, rootHandle);
//read a series of statements into the block
while (parser->current.type != TOY_TOKEN_OPERATOR_BRACE_RIGHT && !match(parser, TOY_TOKEN_EOF)) {
//process the grammar rules
Toy_Ast* stmt = NULL;
makeDeclarationStmt(bucketHandle, parser, &stmt);
//if something went wrong
if (parser->panic) {
synchronize(parser);
Toy_Ast* err = NULL;
Toy_private_emitAstError(bucketHandle, &err);
Toy_private_appendAstBlock(bucketHandle, *rootHandle, err);
continue;
}
Toy_private_appendAstBlock(bucketHandle, *rootHandle, stmt);
}
}
//exposed functions
void Toy_bindParser(Toy_Parser* parser, Toy_Lexer* lexer) {
Toy_resetParser(parser);
parser->lexer = lexer;
advance(parser);
}
Toy_Ast* Toy_scanParser(Toy_Bucket** bucketHandle, Toy_Parser* parser) {
Toy_Ast* rootHandle = NULL;
//check for EOF
if (match(parser, TOY_TOKEN_EOF)) {
Toy_private_emitAstEnd(bucketHandle, &rootHandle);
return rootHandle;
}
makeBlockStmt(bucketHandle, parser, &rootHandle);
//don't emit this error if we're already panicking
if (parser->panic != true && parser->previous.type != TOY_TOKEN_EOF) {
printError(parser, parser->previous, "Expected 'EOF' and the end of the parser scan (possibly an extra '}' was found)");
}
return rootHandle;
}
void Toy_resetParser(Toy_Parser* parser) {
parser->lexer = NULL;
parser->current = ((Toy_Token){TOY_TOKEN_NULL, 0, 0, NULL});
parser->previous = ((Toy_Token){TOY_TOKEN_NULL, 0, 0, NULL});
parser->error = false;
parser->panic = false;
parser->removeAssert = false;
}
void Toy_configureParser(Toy_Parser* parser, bool removeAssert) {
parser->removeAssert = removeAssert;
}