gem5/ext/ply/example/calc/calc.py
Nathan Binkert 44ebb8d3e2 Update to ply 2.3
ext/ply/ply/lex.py:
ext/ply/ply/yacc.py:
ext/ply/CHANGES:
ext/ply/README:
ext/ply/TODO:
ext/ply/doc/ply.html:
ext/ply/example/ansic/clex.py:
ext/ply/example/ansic/cparse.py:
ext/ply/example/calc/calc.py:
ext/ply/example/hedit/hedit.py:
ext/ply/example/optcalc/calc.py:
ext/ply/test/README:
ext/ply/test/calclex.py:
ext/ply/test/lex_doc1.exp:
ext/ply/test/lex_doc1.py:
ext/ply/test/lex_dup1.exp:
ext/ply/test/lex_dup1.py:
ext/ply/test/lex_dup2.exp:
ext/ply/test/lex_dup2.py:
ext/ply/test/lex_dup3.exp:
ext/ply/test/lex_dup3.py:
ext/ply/test/lex_empty.py:
ext/ply/test/lex_error1.py:
ext/ply/test/lex_error2.py:
ext/ply/test/lex_error3.exp:
ext/ply/test/lex_error3.py:
ext/ply/test/lex_error4.exp:
ext/ply/test/lex_error4.py:
ext/ply/test/lex_hedit.exp:
ext/ply/test/lex_hedit.py:
ext/ply/test/lex_ignore.exp:
ext/ply/test/lex_ignore.py:
ext/ply/test/lex_re1.exp:
ext/ply/test/lex_re1.py:
ext/ply/test/lex_rule1.py:
ext/ply/test/lex_token1.py:
ext/ply/test/lex_token2.py:
ext/ply/test/lex_token3.py:
ext/ply/test/lex_token4.py:
ext/ply/test/lex_token5.exp:
ext/ply/test/lex_token5.py:
ext/ply/test/yacc_badargs.exp:
ext/ply/test/yacc_badargs.py:
ext/ply/test/yacc_badprec.exp:
ext/ply/test/yacc_badprec.py:
ext/ply/test/yacc_badprec2.exp:
ext/ply/test/yacc_badprec2.py:
ext/ply/test/yacc_badrule.exp:
ext/ply/test/yacc_badrule.py:
ext/ply/test/yacc_badtok.exp:
ext/ply/test/yacc_badtok.py:
ext/ply/test/yacc_dup.exp:
ext/ply/test/yacc_dup.py:
ext/ply/test/yacc_error1.exp:
ext/ply/test/yacc_error1.py:
ext/ply/test/yacc_error2.exp:
ext/ply/test/yacc_error2.py:
ext/ply/test/yacc_error3.exp:
ext/ply/test/yacc_error3.py:
ext/ply/test/yacc_inf.exp:
ext/ply/test/yacc_inf.py:
ext/ply/test/yacc_missing1.exp:
ext/ply/test/yacc_missing1.py:
ext/ply/test/yacc_nodoc.exp:
ext/ply/test/yacc_nodoc.py:
ext/ply/test/yacc_noerror.exp:
ext/ply/test/yacc_noerror.py:
ext/ply/test/yacc_nop.exp:
ext/ply/test/yacc_nop.py:
ext/ply/test/yacc_notfunc.exp:
ext/ply/test/yacc_notfunc.py:
ext/ply/test/yacc_notok.exp:
ext/ply/test/yacc_notok.py:
ext/ply/test/yacc_rr.exp:
ext/ply/test/yacc_rr.py:
ext/ply/test/yacc_simple.exp:
ext/ply/test/yacc_simple.py:
ext/ply/test/yacc_sr.exp:
ext/ply/test/yacc_sr.py:
ext/ply/test/yacc_term1.exp:
ext/ply/test/yacc_term1.py:
ext/ply/test/yacc_unused.exp:
ext/ply/test/yacc_unused.py:
ext/ply/test/yacc_uprec.exp:
ext/ply/test/yacc_uprec.py:
    Import patch ply.diff
src/arch/isa_parser.py:
    everything is now within the ply package

--HG--
rename : ext/ply/lex.py => ext/ply/ply/lex.py
rename : ext/ply/yacc.py => ext/ply/ply/yacc.py
extra : convert_revision : fca8deabd5c095bdeabd52a1f236ae1404ef106e
2007-05-24 21:54:51 -07:00

105 lines
2.1 KiB
Python

# -----------------------------------------------------------------------------
# calc.py
#
# A simple calculator with variables. This is from O'Reilly's
# "Lex and Yacc", p. 63.
# -----------------------------------------------------------------------------
import sys
sys.path.insert(0,"../..")
tokens = (
'NAME','NUMBER',
)
literals = ['=','+','-','*','/', '(',')']
# Tokens
t_NAME = r'[a-zA-Z_][a-zA-Z0-9_]*'
def t_NUMBER(t):
r'\d+'
try:
t.value = int(t.value)
except ValueError:
print "Integer value too large", t.value
t.value = 0
return t
t_ignore = " \t"
def t_newline(t):
r'\n+'
t.lexer.lineno += t.value.count("\n")
def t_error(t):
print "Illegal character '%s'" % t.value[0]
t.lexer.skip(1)
# Build the lexer
import ply.lex as lex
lex.lex()
# Parsing rules
precedence = (
('left','+','-'),
('left','*','/'),
('right','UMINUS'),
)
# dictionary of names
names = { }
def p_statement_assign(p):
'statement : NAME "=" expression'
names[p[1]] = p[3]
def p_statement_expr(p):
'statement : expression'
print p[1]
def p_expression_binop(p):
'''expression : expression '+' expression
| expression '-' expression
| expression '*' expression
| expression '/' expression'''
if p[2] == '+' : p[0] = p[1] + p[3]
elif p[2] == '-': p[0] = p[1] - p[3]
elif p[2] == '*': p[0] = p[1] * p[3]
elif p[2] == '/': p[0] = p[1] / p[3]
def p_expression_uminus(p):
"expression : '-' expression %prec UMINUS"
p[0] = -p[2]
def p_expression_group(p):
"expression : '(' expression ')'"
p[0] = p[2]
def p_expression_number(p):
"expression : NUMBER"
p[0] = p[1]
def p_expression_name(p):
"expression : NAME"
try:
p[0] = names[p[1]]
except LookupError:
print "Undefined name '%s'" % p[1]
p[0] = 0
def p_error(p):
print "Syntax error at '%s'" % p.value
import ply.yacc as yacc
yacc.yacc()
while 1:
try:
s = raw_input('calc > ')
except EOFError:
break
if not s: continue
yacc.parse(s)