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|
#!/bin/env python3
import sys
import ply.lex as lex
import ply.yacc as yacc
input = open(sys.argv[1]).read()
reserved = {
"function": "FUNCTION",
"if": "IF",
"else": "ELSE",
"return": "RETURN",
"const": "CONST",
"var": "VAR",
"integer": "TYPE_INTEGER",
"string": "TYPE_STRING",
"void": "TYPE_VOID",
}
tokens = [
"OPERATOR_PLUS",
"OPERATOR_MINUS",
"OPERATOR_MULTIPLY",
"OPERATOR_DIVIDE",
"ASSIGN",
"OPERATOR_PIPE",
"OPERATOR_PIPE_REPLACEMENT",
"PARENTHESIS_LEFT",
"PARENTHESIS_RIGHT",
"BRACE_LEFT",
"BRACE_RIGHT",
"BRACKET_LEFT",
"BRACKET_RIGHT",
"BIT_OR",
"NAMESPACE_ACCESSOR",
"COMMA",
"COLON",
"SEMICOLON",
"IDENTIFIER",
"NUMBER",
"STRING",
"COMMENT",
] + list(reserved.values())
t_OPERATOR_PLUS = r'\+'
t_OPERATOR_MINUS = r'-'
t_OPERATOR_MULTIPLY = r'\*'
t_OPERATOR_DIVIDE = r'/'
t_ASSIGN = '='
t_OPERATOR_PIPE = r'\|>'
t_OPERATOR_PIPE_REPLACEMENT = r'\$'
t_PARENTHESIS_LEFT = r'\('
t_PARENTHESIS_RIGHT = r'\)'
t_BRACE_LEFT = r'\['
t_BRACE_RIGHT = r'\]'
t_BRACKET_LEFT = r'{'
t_BRACKET_RIGHT = r'}'
t_BIT_OR = r'\|'
t_NAMESPACE_ACCESSOR = r'\.'
t_COMMA = r','
t_COLON = r':'
t_SEMICOLON = r';'
def t_IDENTIFIER(t):
r'[a-zA-Z][a-zA-Z0-9_]*'
t.type = reserved.get(t.value, 'IDENTIFIER')
return t
def t_NUMBER(t):
r'[0-9]+'
t.value = int(t.value)
return t
def t_STRING(t):
r'(".+"|\'.*\')'
return t
def t_COMMENT(t):
r'//.*'
pass
def t_newline(t):
r'\n+'
t.lexer.lineno += len(t.value)
t_ignore = ' \t'
def t_error(t):
print("undefined: '%s'" % t.value[0])
t.lexer.skip(1)
lexer = lex.lex()
lexer.input(input)
lineno = 0
for token in lexer:
if token.lineno != lineno:
lineno = token.lineno
print("\nLine %s:" % token.lineno)
print('%s: "%s" --' % (token.type, token.value), end=' ')
print("\n")
precedence = (
('left', 'OPERATOR_PLUS', 'OPERATOR_MINUS'),
('left', 'OPERATOR_MULTIPLY', 'OPERATOR_DIVIDE'),
)
def p_statements(p):
'''statements : statement
| statement statements'''
pass
def p_statement(p):
'''statement : variable_declaration_statement
| variable_reassignment_statement'''
pass
# def p_function(p):
# '''function : FUNCTION IDENTIFIER PARENTHESIS_LEFT function_parameters PARENTHESIS_RIGHT COLON return_type BRACKET_LEFT statements BRACKET_RIGHT'''
# pass
def p_variable_declaration_statement(p):
'''variable_declaration_statement : variable_declarator IDENTIFIER COLON variable_type ASSIGN expression SEMICOLON'''
pass
def p_variable_reassignment_statement(p):
'''variable_reassignment_statement : IDENTIFIER ASSIGN expression SEMICOLON'''
pass
def p_variable_declarator(p):
'''variable_declarator : CONST
| VAR'''
pass
def p_variable_type(p):
'''variable_type : TYPE_INTEGER
| TYPE_STRING'''
pass
def p_expression(p):
'''expression : IDENTIFIER
| NUMBER
| STRING
| expression OPERATOR_PLUS expression
| expression OPERATOR_MINUS expression
| expression OPERATOR_MULTIPLY expression
| expression OPERATOR_DIVIDE expression'''
pass
def p_error(p):
print("Syntax error in input!", p)
parser = yacc.yacc()
result = parser.parse(input)
print(result)
|
