Question

I have found a function which implement a switch statement –>

File = open('/file.txt','r')

    String = File.readline()
    String = str(String)
    print String 

    for case in switch(String):
        if case("Head"):
            print "test successed"
            break
        if case("Small"):
            print String
            break
        if case("Big"):
            print String
            break  
        if case():
            print String 
            break 

the String value when I print it is Head, but the switch statement always goes to the last case.. the function works fine apparently because when I changed the String with v = “Head” it worked!!!

any idea what went wrong ?

the switch function –>

class switch(object):
 def __init__(self, value):
    self.value = value
    self.fall = False

 def __iter__(self):
    """Return the match method once, then stop"""
    yield self.match
    raise StopIteration

 def match(self, *args):
    """Indicate whether or not to enter a case suite"""
    if self.fall or not args:
        return True
    elif self.value in args: # changed for v1.5, see below
        self.fall = True
        return True
    else:
        return False

Answer 1

Please don’t ever write code like this. Do it in proper Python style. It’s much easier to read. Anyone coming across usage of that “switch” mess will probably curse you heartily.

with open('/file.txt', 'r') as fp:
    line = fp.readline().rstrip('\n')
    print line

if line == 'Head':
    print "test successed"
elif line == 'Small':
    print line
elif line == 'Big':
    print line
else:
    print line

---

As to why it’s failing, the readline() call will very likely be including a trailing newline character, and 'Head' != 'Head\n'.