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authorNathan Binkert <nate@binkert.org>2009-08-16 13:39:58 -0700
committerNathan Binkert <nate@binkert.org>2009-08-16 13:39:58 -0700
commite1270f81bdc81f5a575b34c2d2c294bdde3e6f4f (patch)
treeb54af3469a338609faf04e67603c5264e79d59a5 /ext/ply/test/yacc_uprec2.py
parentbcaf93d182f43bf72d52104bb909324945904120 (diff)
downloadgem5-e1270f81bdc81f5a575b34c2d2c294bdde3e6f4f.tar.xz
ply: update PLY to version 3.2
Diffstat (limited to 'ext/ply/test/yacc_uprec2.py')
-rw-r--r--ext/ply/test/yacc_uprec2.py63
1 files changed, 63 insertions, 0 deletions
diff --git a/ext/ply/test/yacc_uprec2.py b/ext/ply/test/yacc_uprec2.py
new file mode 100644
index 000000000..73274bfb6
--- /dev/null
+++ b/ext/ply/test/yacc_uprec2.py
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+# -----------------------------------------------------------------------------
+# yacc_uprec2.py
+#
+# A grammar with a bad %prec specifier
+# -----------------------------------------------------------------------------
+import sys
+
+if ".." not in sys.path: sys.path.insert(0,"..")
+import ply.yacc as yacc
+
+from calclex import tokens
+
+# Parsing rules
+
+# dictionary of names
+names = { }
+
+def p_statement_assign(t):
+ 'statement : NAME EQUALS expression'
+ names[t[1]] = t[3]
+
+def p_statement_expr(t):
+ 'statement : expression'
+ 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'
+ t[0] = -t[2]
+
+def p_expression_group(t):
+ 'expression : LPAREN expression RPAREN'
+ t[0] = t[2]
+
+def p_expression_number(t):
+ 'expression : NUMBER'
+ t[0] = t[1]
+
+def p_expression_name(t):
+ 'expression : NAME'
+ try:
+ t[0] = names[t[1]]
+ except LookupError:
+ print("Undefined name '%s'" % t[1])
+ t[0] = 0
+
+def p_error(t):
+ print("Syntax error at '%s'" % t.value)
+
+yacc.yacc()
+
+
+
+