red_always_mafia red_always_mafia - 4 months ago 8
Python Question

Invalid Syntax Error with If statement

So when i try to run this, i get Invalid syntax on the second if statement, highlighting the colon. I don't understand why this is occurring, as far as i can see, they're basically the same. So why does the second if statement return invalid syntax but the first doesnt?

for event in pygame.event.get():
if event.type == MOUSEBUTTONDOWN :
if ROption1Exists == True:
rx, ry = event.pos
if rx >= (100*((X+3)+1)) and rx <= (100*((X+3)+2)) and ry >= (100*(Y+1)) and ry <= (100*(Y+2)):
print('babies')
VarReset()
Pos = ((X+3), Y)
if ROption2Exists == True:
rx, ry = event.pos
if rx >= (100*((X-3)+1)) and rx <= (100*((X-3)+2)) and ry >= (100*((Y+1)) and ry <= (100*(Y+2)):
print('babies')
VarReset()
Pos = ((X-3), Y)

Answer

You have a parenthesis balance problem:

if rx >= (100*((X-3)+1)) and rx <= (100*((X-3)+2)) and ry >= (100*((Y+1)) and ry <= (100*(Y+2)):
#        1    23   2  10           1    23   2  10           1    23   21           2    3   21
#                      ^ all closed              ^ all closed           ^ uhoh

You have one opening parenthesis too many, or one closing parenthesis too few.

You can cut back a little on all those parenthesis, the following suffices:

if rx >= 100*(X-2) and rx <= 100*(X-1) and ry >= 100*(Y+1) and ry <= 100*(Y+2):

You can chain the comparison operators:

if 100*(X-1) >= rx >= 100*(X-2) and 100*(Y+2) >= ry >= 100*(Y+1):

where 100*(X-1) >= rx >= 100*(X-2) is logically the same as 100*(X-1) >= rx and rx >= 100*(X-2) but rx is evaluated only once; all you had to do was invert the <= operators by swapping the operands.

Note that testing for equality to True is rarely required; just drop the == True from your if statements:

if ROption1Exists: