literals = '()'
-tokens = ('NAME', 'AND_OP', 'OR_OP', 'NOT_OP')
+tokens = ('NAME', 'AND_OP', 'OR_OP', 'NOT_OP', 'SP1')
t_NAME = '[a-z][a-z0-9_]*'
t_NOT_OP = '!'
-t_ignore = '[ \t]+'
+t_SP1 = '[ \t]+'
def t_error(t):
"""Avoid warnings on stderr"""
"""expression : NAME"""
p[0] = ('NAME', p[1])
+def p_expression_and_and(p):
+ """expression : expression SP0 AND_OP AND_OP SP0 expression"""
+ p[0] = ('AND', p[1], p[6])
+
def p_expression_and(p):
- """expression : expression AND_OP expression"""
- p[0] = ('AND', p[1], p[3])
+ """expression : expression SP0 AND_OP SP0 expression"""
+ p[0] = ('AND', p[1], p[5])
-def p_expression_not(p):
- """expression : NOT_OP expression"""
- p[0] = ('NOT', p[2])
+def p_expression_op_word(p):
+ """expression : l_expression op_word r_expression"""
+ if p[2] in ('AND', 'and'):
+ p[0] = ('AND', p[1], p[3])
+ elif p[2] in ('OR', 'or'):
+ p[0] = ('OR', p[1], p[3])
+
+def p_expression_or_or(p):
+ """expression : expression SP0 OR_OP OR_OP SP0 expression"""
+ p[0] = ('OR', p[1], p[6])
def p_expression_or(p):
- """expression : expression OR_OP expression"""
- p[0] = ('OR', p[1], p[3])
+ """expression : expression SP0 OR_OP SP0 expression"""
+ p[0] = ('OR', p[1], p[5])
+
+def p_expression_not(p):
+ """expression : NOT_OP SP0 expression"""
+ p[0] = ('NOT', p[3])
+
+def p_expression_in_parens(p):
+ """expression : expression_parens"""
+ p[0] = p[1]
+
+def p_l_expression(p):
+ """l_expression : expression_parens
+ | expression SP1
+ """
+ if len(p) == 2:
+ p[0] = p[1]
+ elif len(p) == 3:
+ p[0] = p[1]
+ else:
+ raise ValueError(p)
+
+def p_r_expression(p):
+ """r_expression : expression_parens
+ | SP1 expression
+ """
+ if len(p) == 2:
+ p[0] = p[1]
+ elif len(p) == 3:
+ p[0] = p[2]
+ else:
+ raise ValueError(p)
def p_expression_parens(p):
- """expression : '(' expression ')'"""
- p[0] = ('PARENS', p[2])
+ """expression_parens : '(' SP0 expression SP0 ')'"""
+ p[0] = ('PARENS', p[3])
+
+def p_op_word(p):
+ """op_word : NAME"""
+ if p[1] in ('AND', 'and', 'OR', 'or'):
+ p[0] = p[1]
+ else:
+ raise SyntaxError
+
+def p_SP0(p):
+ """SP0 : SP1
+ | empty
+ """
+
+def p_empty(p):
+ """empty :"""
def p_error(p):
"""Avoid warnings on stderr"""