diff ply-3.8/test/yacc_error6.py @ 7267:343ff337a19b

<ais523> ` tar -xf ply-3.8.tar.gz
author HackBot
date Wed, 23 Mar 2016 02:40:16 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ply-3.8/test/yacc_error6.py	Wed Mar 23 02:40:16 2016 +0000
@@ -0,0 +1,80 @@
+# -----------------------------------------------------------------------------
+# yacc_error6.py
+#
+# Panic mode recovery test
+# -----------------------------------------------------------------------------
+import sys
+
+if ".." not in sys.path: sys.path.insert(0,"..")
+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)
+""")
+
+
+
+
+
+