Re: Execute commands from file
Steve Holden schrieb [ difference between exec open(fname).read() and for line in open(fname): exec line ] So it seems to depend on the way the file is read. It depends on the way the lines of the file are executed, not how they are read. Could you elaborate a little bit more on the difference? I assumed that because read() reads the whole file, the body of my function sowhat() is present, so that it can be parsed while the invocation of exec is still running. If it is read and exec'd line by line, the definition of the function is still left open at the moment exec() ends, causing the EOF error. Hence my statement, it depends on the way the file is read. And you may remember the original poster was proposing this: inp = open(cmd_file) for line in inp: exec line As for your first example, why not just use execfile() ? I assume that execfile(fname) is equivalent to exec open(fname).read() ? Regards Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
Martin Blume wrote: Steve Holden schrieb [ difference between exec open(fname).read() and for line in open(fname): exec line ] So it seems to depend on the way the file is read. It depends on the way the lines of the file are executed, not how they are read. Could you elaborate a little bit more on the difference? I assumed that because read() reads the whole file, the body of my function sowhat() is present, so that it can be parsed while the invocation of exec is still running. If it is read and exec'd line by line, the definition of the function is still left open at the moment exec() ends, causing the EOF error. Hence my statement, it depends on the way the file is read. I simply meant that the whole source has to be presented to the exec statement and not chunked into lines. Clearly I could read all the source in with lines = open(cmd_file).readlines() but if you then proceed to try and execute the source line by line as in for l in lines: exec l you will hit problems because of the disjoint nature of the execution which will breal up indented suites and so on. I was probably just a little over-zealous in pursuing correct English usage, in which case please accept my apology. And you may remember the original poster was proposing this: inp = open(cmd_file) for line in inp: exec line As for your first example, why not just use execfile() ? I assume that execfile(fname) is equivalent to exec open(fname).read() ? Pretty much. 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
Steve Holden schrieb I simply meant that the whole source has to be presented to the exec statement and not chunked into lines. That's what I meant: With exec open(f).read() it is not broken into several exec invocations. I was probably just a little over-zealous in pursuing correct English usage, in which case please accept my apology. The apology is on my part, I didn't explain my thinking clearly enough. Thanks for your explanations. Makes my newbie understanding of Python much more robust. Regards Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
On Fri, 18 May 2007 04:45:30, Dennis Lee Bieber [EMAIL PROTECTED] wrote On 17 May 2007 13:12:10 -0700, i3dmaster [EMAIL PROTECTED] declaimed the following in comp.lang.python: 'b' is generally useful on systems that don't treat binary and text files differently. It will improve portability. b is needed for binary files on systems that /do/ treat binary differently from text. And it does add to portability only in that it has no effect on those that treat all files the same. However, as I recall the thread, the intent is to process text lines from a file -- and using b is going to affect how the line endings are being treated. Yes that was my understanding too, Dennis, and the reason I queried it in the first place. I had to remove the b option in order to get the sample code to work under Windows, because the standard line termination under Windows is carriage return + linefeed (\r\n). Of course if I manually edit the command file so that it only has a linefeed character at the end of each line, the binary mode works. So I think i3dmaster's method is only portable as long as the command file is created with unix-style line termination. -- Doug Woodrow -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
On May 16, 1:05 pm, Steve Holden [EMAIL PROTECTED] wrote: Martin Blume wrote: tmp123 schrieb We have very big files with python commands (more or less, 50 commands each file). It is possible to execute them command by command, inp = open(cmd_file) for line in inp: exec line might help. You don't get quite the same feeling as like if the commands was typed one after the other in a interactive session, but perhaps this helps. Warning: the code above is without any error checks. You might also run into security problems, the example above assumes you trust your input. HTH. YMMV. Martin The problem with this approach is that each line executes without any connection to the environment created by previous lies. Try it on a file that reads something like xxx = 42 print xxx and you will see NameError raised because the assignment hasn't affected the environment for the print statement. 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading cat file: x = 100 print x cat file.py: #!/usr/bin/python2.4 import os.path import sys file, ext = os.path.splitext(sys.argv[0]) f = open(file,'rb') for i in f: exec i ./file.py 100 Don't see the problem though. -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
On Thu, 17 May 2007 00:30:23, i3dmaster [EMAIL PROTECTED] wrote f = open(file,'rb') for i in f: exec i Why are you opening the file in binary mode? -- Doug Woodrow -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
i3dmaster wrote: On May 16, 1:05 pm, Steve Holden [EMAIL PROTECTED] wrote: Martin Blume wrote: tmp123 schrieb We have very big files with python commands (more or less, 50 commands each file). It is possible to execute them command by command, inp = open(cmd_file) for line in inp: exec line might help. You don't get quite the same feeling as like if the commands was typed one after the other in a interactive session, but perhaps this helps. Warning: the code above is without any error checks. You might also run into security problems, the example above assumes you trust your input. HTH. YMMV. Martin The problem with this approach is that each line executes without any connection to the environment created by previous lies. Try it on a file that reads something like xxx = 42 print xxx and you will see NameError raised because the assignment hasn't affected the environment for the print statement. 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading cat file: x = 100 print x cat file.py: #!/usr/bin/python2.4 import os.path import sys file, ext = os.path.splitext(sys.argv[0]) f = open(file,'rb') for i in f: exec i ./file.py 100 Don't see the problem though. No, because there isn't one. Now try adding a function definition and see how well it works. 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
Steve Holden a écrit :
i3dmaster wrote:
On May 16, 1:05 pm, Steve Holden [EMAIL PROTECTED] wrote:
Martin Blume wrote:
tmp123 schrieb
We have very big files with python commands
(more or less, 50 commands each file).
It is possible to execute them command by command,
inp = open(cmd_file)
for line in inp:
exec line
The problem with this approach is that each line executes without any
connection to the environment created by previous lies.
Try it on a file that reads something like
xxx = 42
print xxx
cat file:
x = 100
print x
cat file.py:
#!/usr/bin/python2.4
import os.path
import sys
file, ext = os.path.splitext(sys.argv[0])
f = open(file,'rb')
for i in f:
exec i
./file.py
100
Don't see the problem though.
No, because there isn't one. Now try adding a function definition and
see how well it works.
regards
Steve
This is just a problem with indentation and blocks of code, the
followong will do :
commands = open(commands)
namespace, block = {},
for line in commands :
line=line[:-1]
if not line : continue
if line[0].isspace() :
block += '\n' + line
continue
else :
if block.strip() :
exec block in namespace
block = line
exec block in namespace
print dict((k, v) for k, v in namespace.items() if k != __builtins__)
with commands containing :
x = 5
def toto(arg) :
print arg
def inner() :
print arg*arg
inner()
toto(x)
output :
5
25
{'x': 5, 'toto': function toto at 0x01D30C70}
(sorry Steve for the private mail)
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Re: Execute commands from file
Steve Holden schrieb Try it on a file that reads something like xxx = 42 print xxx and you will see NameError raised because the assignment hasn't affected the environment for the print statement. [...] No, because there isn't one. Now try adding a function definition and see how well it works. C:\tempmore question.py xxx=42 print xxx def sowhat(): print xxx print xxx C:\tempc:\programme\python\python Python 2.4 (#60, Nov 30 2004, 11:49:19) [MSC v.1310 32 bit (Intel)] on win32 Type help, copyright, credits or license for more information. exec open(question.py).read() 42 42 sowhat() 42 xxx 42 Seems to work great to me. OTOH, this doesn't: inp=open(question.py) for l in inp: ... exec l ... 42 Traceback (most recent call last): File stdin, line 2, in ? File string, line 1 def sowhat(): ^ SyntaxError: unexpected EOF while parsing So it seems to depend on the way the file is read. Regards Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
On May 17, 3:02 am, Douglas Woodrow [EMAIL PROTECTED] wrote: On Thu, 17 May 2007 00:30:23, i3dmaster [EMAIL PROTECTED] wrote f = open(file,'rb') for i in f: exec i Why are you opening the file in binary mode? -- Doug Woodrow 'b' is generally useful on systems that don't treat binary and text files differently. It will improve portability. -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
Martin Blume wrote: Steve Holden schrieb Try it on a file that reads something like xxx = 42 print xxx and you will see NameError raised because the assignment hasn't affected the environment for the print statement. [...] No, because there isn't one. Now try adding a function definition and see how well it works. C:\tempmore question.py xxx=42 print xxx def sowhat(): print xxx print xxx C:\tempc:\programme\python\python Python 2.4 (#60, Nov 30 2004, 11:49:19) [MSC v.1310 32 bit (Intel)] on win32 Type help, copyright, credits or license for more information. exec open(question.py).read() 42 42 sowhat() 42 xxx 42 Seems to work great to me. OTOH, this doesn't: inp=open(question.py) for l in inp: ... exec l ... 42 Traceback (most recent call last): File stdin, line 2, in ? File string, line 1 def sowhat(): ^ SyntaxError: unexpected EOF while parsing So it seems to depend on the way the file is read. It depends on the way the lines of the file are executed, not how they are read. And you may remember the original poster was proposing this: inp = open(cmd_file) for line in inp: exec line As for your first example, why not just use execfile() ? 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading -- http://mail.python.org/mailman/listinfo/python-list
Execute commands from file
Hello, Thanks for your time. We have very big files with python commands (more or less, 50 commands each file). It is possible to execute them command by command, like if the commands was typed one after the other in a interactive session? ( Better using command flags than with an small script like while 1: input()) Thanks a lot. -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
In [EMAIL PROTECTED], tmp123 wrote: We have very big files with python commands (more or less, 50 commands each file). It is possible to execute them command by command, like if the commands was typed one after the other in a interactive session? Take a look at the `code` module in the standard library: In [31]: code? Type: module Base Class: type 'module' String Form:module 'code' from '/usr/lib/python2.4/code.pyc' Namespace: Interactive File: /usr/lib/python2.4/code.py Docstring: Utilities needed to emulate Python's interactive interpreter. Ciao, Marc 'BlackJack' Rintsch -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
tmp123 wrote: Hello, Thanks for your time. We have very big files with python commands (more or less, 50 commands each file). Those are BIG programs. Presumably other programs are writing them? It is possible to execute them command by command, like if the commands was typed one after the other in a interactive session? You need to look for pdb, the interactive Python debugger. This is capable of single-step operations, and supports breakpoints. ( Better using command flags than with an small script like while 1: input()) Thanks a lot. You are pretty much going to have to run pdb then trigger your code by calling a pdb method with a function in your code as an argument, if I am remembering correctly how it works. 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
tmp123 schrieb We have very big files with python commands (more or less, 50 commands each file). It is possible to execute them command by command, inp = open(cmd_file) for line in inp: exec line might help. You don't get quite the same feeling as like if the commands was typed one after the other in a interactive session, but perhaps this helps. Warning: the code above is without any error checks. You might also run into security problems, the example above assumes you trust your input. HTH. YMMV. Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: Execute commands from file
Martin Blume wrote: tmp123 schrieb We have very big files with python commands (more or less, 50 commands each file). It is possible to execute them command by command, inp = open(cmd_file) for line in inp: exec line might help. You don't get quite the same feeling as like if the commands was typed one after the other in a interactive session, but perhaps this helps. Warning: the code above is without any error checks. You might also run into security problems, the example above assumes you trust your input. HTH. YMMV. Martin The problem with this approach is that each line executes without any connection to the environment created by previous lies. Try it on a file that reads something like xxx = 42 print xxx and you will see NameError raised because the assignment hasn't affected the environment for the print statement. 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 -- Asciimercial - Get on the web: Blog, lens and tag your way to fame!! holdenweb.blogspot.comsquidoo.com/pythonology tagged items: del.icio.us/steve.holden/python All these services currently offer free registration! -- Thank You for Reading -- http://mail.python.org/mailman/listinfo/python-list
