[Tutor] Indentation
Bob Gailer
bgailer@alum.rpi.edu
Wed Jun 4 12:41:16 2003
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At 04:39 PM 6/4/2003 +0200, Guillaume wrote:
>I don't understand what's the meaning of this word and his roll in a prog:
>what does
>indentation bring to a prog?
roll? did you mean role?
"Indent" means to provide some spaces on the left of a line. Why? Certain
python statements (called Compound Statements in the langref) control the
execution of 1 or more subsequent statements:
for i in range(3):
print i
i = 0
while i < 3:
i += 1
print i
print 'Done'
if i > 3:
print 'yes'
a = 4
else:
print 'no'
a = 5
also applies to try-except; try-finally; def and class
To tell the interpreter that statements are under control of a Compound
Statement one indents them. Thus in the while example above i += 1 and
print i are indented two spaces, showing that they are to be repeated while
i < 3. The only rule is that indentation must be consistent within a set of
statements. Thus
if i > 3:
print 'yes'
a = 4
else:
print 'no'
a = 5
is acceptable, whereas
if i > 3:
print 'yes'
a = 4
else:
print 'no'
a = 5
is not.
Bob Gailer
bgailer@alum.rpi.edu
303 442 2625
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At 04:39 PM 6/4/2003 +0200, Guillaume wrote:<br>
<blockquote type=cite class=cite cite><font face="Arial Narrow, Helvetica">I
don't understand what's the meaning of this word and his roll in a prog:
what does </font><br>
<font face="Arial Narrow, Helvetica">indentation bring to a
prog?</font></blockquote><br>
roll? did you mean role?<br><br>
"Indent" means to provide some spaces on the left of a line.
Why? Certain python statements (called Compound Statements in the
langref) control the execution of 1 or more subsequent
statements:<br><br>
for i in range(3):<br>
print i<br><br>
i = 0<br>
while i < 3:<br>
i += 1<br>
print i<br>
print 'Done'<br><br>
if i > 3:<br>
print 'yes'<br>
a = 4<br>
else:<br>
print 'no'<br>
a = 5<br><br>
also applies to try-except; try-finally; def and class<br><br>
To tell the interpreter that statements are under control of a Compound
Statement one indents them. Thus in the while example above i += 1 and
print i are indented two spaces, showing that they are to be repeated
while i < 3. The only rule is that indentation must be consistent
within a set of statements. Thus<br><br>
if i > 3:<br>
print 'yes'<br>
a = 4<br>
else:<br>
print 'no'<br>
a = 5<br><br>
is acceptable, whereas<br><br>
if i > 3:<br>
print 'yes'<br>
a = 4<br>
else:<br>
print 'no'<br>
a = 5<br><br>
is not.<br><br>
<x-sigsep><p></x-sigsep>
Bob Gailer<br>
bgailer@alum.rpi.edu<br>
303 442 2625<br>
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