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-rw-r--r--tests/yacc_error6.py77
1 files changed, 77 insertions, 0 deletions
diff --git a/tests/yacc_error6.py b/tests/yacc_error6.py
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+++ b/tests/yacc_error6.py
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+# -----------------------------------------------------------------------------
+# yacc_error6.py
+#
+# Panic mode recovery test
+# -----------------------------------------------------------------------------
+import ply.yacc as yacc
+
+from calclex import tokens
+
+# Parsing rules
+precedence = (
+ ('left','PLUS','MINUS'),
+ ('left','TIMES','DIVIDE'),
+ ('right','UMINUS'),
+ )
+
+def p_statements(t):
+ 'statements : statements statement'
+ pass
+
+def p_statements_1(t):
+ 'statements : statement'
+ pass
+
+def p_statement_assign(p):
+ 'statement : LPAREN NAME EQUALS expression RPAREN'
+ print("%s=%s" % (p[2],p[4]))
+
+def p_statement_expr(t):
+ 'statement : LPAREN expression RPAREN'
+ print(t[1])
+
+def p_expression_binop(t):
+ '''expression : expression PLUS expression
+ | expression MINUS expression
+ | expression TIMES expression
+ | expression DIVIDE expression'''
+ if t[2] == '+' : t[0] = t[1] + t[3]
+ elif t[2] == '-': t[0] = t[1] - t[3]
+ elif t[2] == '*': t[0] = t[1] * t[3]
+ elif t[2] == '/': t[0] = t[1] / t[3]
+
+def p_expression_uminus(t):
+ 'expression : MINUS expression %prec UMINUS'
+ t[0] = -t[2]
+
+def p_expression_number(t):
+ 'expression : NUMBER'
+ t[0] = t[1]
+
+def p_error(p):
+ if p:
+ print("Line %d: Syntax error at '%s'" % (p.lineno, p.value))
+ # Scan ahead looking for a name token
+ while True:
+ tok = parser.token()
+ if not tok or tok.type == 'RPAREN':
+ break
+ if tok:
+ parser.restart()
+ return None
+
+parser = yacc.yacc()
+import calclex
+calclex.lexer.lineno=1
+
+parser.parse("""
+(a = 3 + 4)
+(b = 4 + * 5 - 6 + *)
+(c = 10 + 11)
+""")
+
+
+
+
+
+