(curses) issue about inch()

[Steve Holden]

Jimmy wrote:
> On Sep 17, 12:07 am, Steve Holden <st... at holdenweb.com> wrote:
>> Jimmy wrote:
>>> hi, all
>>> I attempt to use the function inch() to get the character at the
>>> current position, and compare it with a particular character like :
>>> if screen.inch(x,y) == 'F'
>>> but this method doesn't seem work, can anyone tell me the reason and
>>> how to corrent it
>>> thanks
>> The reason is because something is wrong, and yo fix it by correcting
>> that issue.
>>
>> In other words, if you could be a bit more specific about *how* it
>> doesn't work (like, show us the code you are running,a nd any error
>> messages or evidence of incorrect results) you will be able to get some
>> help that actually helps you.
>>
>> Would you go to a car repair shop with faulty brakes and just tell them
>> "my car isn't working"?
>>
>> regards
>>   Steve
>> --
>> Steve Holden        +1 571 484 6266   +1 800 494 3119
>> Holden Web LLC/Ltd          http://www.holdenweb.com
>> Skype: holdenweb      http://del.icio.us/steve.holden
>>
>> Sorry, the dog ate my .sigline
> 
> thanks,
> actually i'm writing a game like mine,the pertainign code is:
> 
> def mark():
> 	"""mark the bomb"""
> 	(row, col) = gb.scrn.getyx()
> 	x = gb.scrn.inch(row,col)
> 	if x == 'F':
> 		gb.scrn.addch(row,col, 'X',curses.color_pair(3))
> 	else:
> 		gb.scrn.addch(row,col, 'F',curses.color_pair(3))
> 
> 	gb.scrn.move(row,col)
> 	gb.scrn.refresh()
> 
> the situation is x never equals 'F', even when it really is!
> I checked the mannual and found the return value of inch() consists
> the actual character(low 8bits)
> and the attributes, so I tried the following: (x<<24)>>24,cause I
> guess the int is 32bits long.
> but it still doesn't work :(
> 
Well first of all, thanks for reading the manual.

Let's suppose the value you are receiving is 1234 (clearly more than 8 
bits). Unfortunately for you, recent versions of Python don't just use 
32-bit integers, but extend the values into Python's long values where 
necessary. See:

 >>> (1234<<24)>>24
1234L
 >>>

What you really need is a logical and with 255:

 >>> 1234 & 255
210
 >>>

Hope this helps.

regards
  Steve
-- 
Steve Holden        +1 571 484 6266   +1 800 494 3119
Holden Web LLC/Ltd           http://www.holdenweb.com
Skype: holdenweb      http://del.icio.us/steve.holden

Sorry, the dog ate my .sigline