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⇤ ← Revision 1 as of 2005-09-03 01:32:31
Size: 281
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Size: 1471
Comment: Add the output function
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{{{#!python def output(*args, **kwds): """Functional replacement for the print statement >>> output(1, 2, 3) 1 2 3 >>> output(1, 2, 3, sep='') 123 >>> output(1, 2, 3, sep=', ') 1, 2, 3 >>> output(1, 2, 3, end='Alternate line ending') 1 2 3Alternate line ending >>> import sys >>> output(1, 2, 3, stream=sys.stderr) 1 2 3 >>> output(*range(10)) 0 1 2 3 4 5 6 7 8 9 >>> output(*(x*x for x in range(10))) 0 1 4 9 16 25 36 49 64 81 """ # Parse the keyword-only optional arguments defaults = { "sep": " ", "end": "\n", "stream": sys.stdout, } for name, default in defaults.items(): item = None try: item = kwds[name] except KeyError: pass if item is None: kwds[name] = default sep, end, stream = kwds["sep"], kwds["end"], kwds["stream"] # Perform the print operation without building the whole string for arg in args[:1]: stream.write(str(arg)) for arg in args[1:]: stream.write(sep) stream.write(str(arg)) stream.write(end) }}} |
This page discusses the benefits of replacing the current print statement with an equivalent builtin. The output function presented below does everything the print statement does without requiring an hacking of the grammar, and also makes a number of things significantly easier.
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1 def output(*args, **kwds):
2 """Functional replacement for the print statement
3
4 >>> output(1, 2, 3)
5 1 2 3
6 >>> output(1, 2, 3, sep='')
7 123
8 >>> output(1, 2, 3, sep=', ')
9 1, 2, 3
10 >>> output(1, 2, 3, end='Alternate line ending')
11 1 2 3Alternate line ending
12 >>> import sys
13 >>> output(1, 2, 3, stream=sys.stderr)
14 1 2 3
15 >>> output(*range(10))
16 0 1 2 3 4 5 6 7 8 9
17 >>> output(*(x*x for x in range(10)))
18 0 1 4 9 16 25 36 49 64 81
19 """
20 # Parse the keyword-only optional arguments
21 defaults = {
22 "sep": " ",
23 "end": "\n",
24 "stream": sys.stdout,
25 }
26 for name, default in defaults.items():
27 item = None
28 try:
29 item = kwds[name]
30 except KeyError:
31 pass
32 if item is None:
33 kwds[name] = default
34 sep, end, stream = kwds["sep"], kwds["end"], kwds["stream"]
35 # Perform the print operation without building the whole string
36 for arg in args[:1]:
37 stream.write(str(arg))
38 for arg in args[1:]:
39 stream.write(sep)
40 stream.write(str(arg))
41 stream.write(end)