Why is the print statement in the class executed when an object isn't even created?
1
When I run the code below the output is "hello".
However, the print statement is part of the class pl, and i never created an instance of the class pl, so why is the print statement being executed?
class pl:
def __init__(self,a,b):
self.aa=a
self.bb=b
print("hello")
python python-3.x class
edited Nov 22 at 18:59
timgeb
48.8k116390
asked Nov 22 at 17:50
user3124200
704
add a comment |
1
When I run the code below the output is "hello".
However, the print statement is part of the class pl, and i never created an instance of the class pl, so why is the print statement being executed?
class pl:
def __init__(self,a,b):
self.aa=a
self.bb=b
print("hello")
python python-3.x class
edited Nov 22 at 18:59
timgeb
48.8k116390
asked Nov 22 at 17:50
user3124200
704
add a comment |
1
1
1
When I run the code below the output is "hello".
However, the print statement is part of the class pl, and i never created an instance of the class pl, so why is the print statement being executed?
class pl:
def __init__(self,a,b):
self.aa=a
self.bb=b
print("hello")
python python-3.x class
edited Nov 22 at 18:59
timgeb
48.8k116390
asked Nov 22 at 17:50
user3124200
704
When I run the code below the output is "hello".
However, the print statement is part of the class pl, and i never created an instance of the class pl, so why is the print statement being executed?
class pl:
def __init__(self,a,b):
self.aa=a
self.bb=b
print("hello")
python python-3.x class
python python-3.x class
edited Nov 22 at 18:59
timgeb
48.8k116390
asked Nov 22 at 17:50
user3124200
704
edited Nov 22 at 18:59
timgeb
48.8k116390
asked Nov 22 at 17:50
user3124200
704
edited Nov 22 at 18:59
timgeb
48.8k116390
edited Nov 22 at 18:59
timgeb
48.8k116390
edited Nov 22 at 18:59
timgeb
48.8k116390
48.8k116390
asked Nov 22 at 17:50
user3124200
704
asked Nov 22 at 17:50
user3124200
704
asked Nov 22 at 17:50
user3124200
704
704
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
7
Class bodies (even nested class bodies) are executed at import time (as opposed to functions or methods).
Demo script:
class Upper:
print('Upper')
class Mid:
print('Mid')
def method(self):
class Low:
print('Low')
print('method')
Output:
$ python3
>>> import demo
Upper
Mid
answered Nov 22 at 17:53
timgeb
48.8k116390
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
@user3124200methodis an attribute of the classUpper.print('method')is a print statement executed in the body ofmethod, not in the body ofLow. You can work this out by looking at the indentation levels.
– timgeb
Nov 22 at 18:38
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
7
Class bodies (even nested class bodies) are executed at import time (as opposed to functions or methods).
Demo script:
class Upper:
print('Upper')
class Mid:
print('Mid')
def method(self):
class Low:
print('Low')
print('method')
Output:
$ python3
>>> import demo
Upper
Mid
answered Nov 22 at 17:53
timgeb
48.8k116390
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
@user3124200methodis an attribute of the classUpper.print('method')is a print statement executed in the body ofmethod, not in the body ofLow. You can work this out by looking at the indentation levels.
– timgeb
Nov 22 at 18:38
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
add a comment |
7
Class bodies (even nested class bodies) are executed at import time (as opposed to functions or methods).
Demo script:
class Upper:
print('Upper')
class Mid:
print('Mid')
def method(self):
class Low:
print('Low')
print('method')
Output:
$ python3
>>> import demo
Upper
Mid
answered Nov 22 at 17:53
timgeb
48.8k116390
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
@user3124200methodis an attribute of the classUpper.print('method')is a print statement executed in the body ofmethod, not in the body ofLow. You can work this out by looking at the indentation levels.
– timgeb
Nov 22 at 18:38
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
add a comment |
7
7
7
Class bodies (even nested class bodies) are executed at import time (as opposed to functions or methods).
Demo script:
class Upper:
print('Upper')
class Mid:
print('Mid')
def method(self):
class Low:
print('Low')
print('method')
Output:
$ python3
>>> import demo
Upper
Mid
answered Nov 22 at 17:53
timgeb
48.8k116390
Class bodies (even nested class bodies) are executed at import time (as opposed to functions or methods).
Demo script:
class Upper:
print('Upper')
class Mid:
print('Mid')
def method(self):
class Low:
print('Low')
print('method')
Output:
$ python3
>>> import demo
Upper
Mid
answered Nov 22 at 17:53
timgeb
48.8k116390
answered Nov 22 at 17:53
timgeb
48.8k116390
answered Nov 22 at 17:53
timgeb
48.8k116390
answered Nov 22 at 17:53
timgeb
48.8k116390
48.8k116390
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
@user3124200methodis an attribute of the classUpper.print('method')is a print statement executed in the body ofmethod, not in the body ofLow. You can work this out by looking at the indentation levels.
– timgeb
Nov 22 at 18:38
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
add a comment |
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
@user3124200methodis an attribute of the classUpper.print('method')is a print statement executed in the body ofmethod, not in the body ofLow. You can work this out by looking at the indentation levels.
– timgeb
Nov 22 at 18:38
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
Thanks! Does 'def method(self):' belong to class Mid or class Upper? Based on indentation i would say it belongs to upper, but it's below/within Mid so I'm confused. Also am I correct in saying that print('method') doesn't belong to class Low?
– user3124200
Nov 22 at 18:16
@user3124200
method is an attribute of the class Upper. print('method') is a print statement executed in the body of method, not in the body of Low. You can work this out by looking at the indentation levels.– timgeb
Nov 22 at 18:38
@user3124200
method is an attribute of the class Upper. print('method') is a print statement executed in the body of method, not in the body of Low. You can work this out by looking at the indentation levels.– timgeb
Nov 22 at 18:38
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@user3124200 did that clear everything up?
– timgeb
Nov 22 at 19:44
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@timegb Thanks! I am confused on the following point though: 1) print('Upper') is executed as part of the Upper class and then 2) print('Mid') is executed as part of the Mid class and then 3) method is an attribute of the class upper. I'm confused at how the code jumps around from having statements belong to the upper class, then the mid class, and then the upper class again. Shouldn't everything defined within one class first & then within a nested class, and then within another sub class etc. How would you express the above code if python used curly brackets rather than indentation?
– user3124200
Nov 23 at 7:14
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
@user3124200 does this pseudo-code help?
– timgeb
Nov 23 at 9:31
add a comment |
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