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|
package parser
import (
"jinx/pkg/lang/ast"
"jinx/pkg/lang/scanner/token"
)
type Parser struct {
tokens []token.Token
pos int
}
func New(tokens []token.Token) *Parser {
return &Parser{tokens: tokens, pos: 0}
}
func (p *Parser) Parse() (ast.Program, error) {
program := ast.Program{}
for p.pos < len(p.tokens) {
stmt, err := p.parseStmt()
if err != nil {
return ast.Program{}, err
}
if err = p.parseStmtEnd(); err != nil {
return ast.Program{}, err
}
program.Stmts = append(program.Stmts, stmt)
}
return program, nil
}
func (p *Parser) parseBlock() (ast.BlockNode, error) {
braceTok, err := p.expect(token.LBrace)
if err != nil {
return ast.BlockNode{}, err
}
stmts := []ast.Stmt{}
for {
stmt, err := p.parseStmt()
if err != nil {
return ast.BlockNode{}, err
}
stmts = append(stmts, stmt)
if err = p.parseStmtEnd(); err != nil {
return ast.BlockNode{}, err
}
if p.peek().Kind == token.RBrace {
break
}
}
if _, err := p.expect(token.RBrace); err != nil {
return ast.BlockNode{}, err
}
return ast.BlockNode{
At: braceTok.At,
Stmts: stmts,
}, nil
}
func (p *Parser) parseIdent() (ast.IdentNode, error) {
tok, err := p.expect(token.Ident)
if err != nil {
return ast.IdentNode{}, err
}
return ast.IdentNode{
At: tok.At,
Value: tok.Data.(string),
}, nil
}
func (p *Parser) next() token.Token {
p.pos++
return p.tokens[p.pos-1]
}
func (p *Parser) expect(kind token.TokenKind) (token.Token, error) {
tok := p.next()
if tok.Kind != kind {
return token.Token{}, ErrExpectedToken{
At: tok.At,
Wanted: kind,
Got: tok,
}
}
return tok, nil
}
func (p *Parser) peek() token.Token {
return p.tokens[p.pos]
}
|
