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author | Greg Ward <gward@python.net> | 2003-05-03 20:41:37 (GMT) |
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committer | Greg Ward <gward@python.net> | 2003-05-03 20:41:37 (GMT) |
commit | 649625bc05731f754d3ba0f3d111e3e2d6a81614 (patch) | |
tree | b2905746799574c9d505d0051ec1e2a3cd2adc00 /Doc | |
parent | 1f53517a8c2dd7662d1eeff7e2ff6e0cd6aaae90 (diff) | |
download | cpython-649625bc05731f754d3ba0f3d111e3e2d6a81614.zip cpython-649625bc05731f754d3ba0f3d111e3e2d6a81614.tar.gz cpython-649625bc05731f754d3ba0f3d111e3e2d6a81614.tar.bz2 |
Rename "The Tao of Option Parsing" section to "Philosophy".
Remove first-person usage from it. Various wording tweaks.
Diffstat (limited to 'Doc')
-rw-r--r-- | Doc/lib/liboptparse.tex | 60 |
1 files changed, 30 insertions, 30 deletions
diff --git a/Doc/lib/liboptparse.tex b/Doc/lib/liboptparse.tex index f088f88..8f9de1e 100644 --- a/Doc/lib/liboptparse.tex +++ b/Doc/lib/liboptparse.tex @@ -65,15 +65,13 @@ options: That's just a taste of the flexibility \module{optparse} gives you in parsing your command-line. -\subsection{The Tao of Option Parsing\label{optparse-tao}} +\subsection{Philosophy\label{optparse-philosophy}} -\module{optparse} is an implementation of what I have always -considered the most obvious, straightforward, and user-friendly way to -design a user interface for command-line programs. In short, I have -fairly firm ideas of the Right Way (and the many Wrong Ways) to do -argument parsing, and \module{optparse} reflects many of those ideas. -This section is meant to explain this philosophy, which in turn is -heavily influenced by the \UNIX{} and GNU toolkits. +The purpose of \module{optparse} is to make it very easy to provide the +most standard, obvious, straightforward, and user-friendly user +interface for \UNIX{} command-line programs. The \module{optparse} +philosophy is heavily influenced by the \UNIX{} and GNU toolkits, and +this section is meant to explain that philosophy. \subsubsection{Terminology\label{optparse-terminology}} @@ -88,8 +86,8 @@ Python, arguments are elements of being executed; in the context of parsing arguments, it's not very important.) \UNIX{} shells also use the term ``word''. -It's occasionally desirable to substitute an argument list other -than \var{sys.argv[1:]}, so you should read ``argument'' as ``an element of +It is occasionally desirable to use an argument list other than +\var{sys.argv[1:]}, so you should read ``argument'' as ``an element of \var{sys.argv[1:]}, or of some other list provided as a substitute for \var{sys.argv[1:]}''. @@ -120,13 +118,13 @@ than \var{sys.argv[1:]}, so you should read ``argument'' as ``an element of \programopt{/f}, \programopt{/file}. \end{itemize} -These option syntaxes are not supported by \module{optparse}, and they -never will be. (If you really want to use one of those option -syntaxes, you'll have to subclass OptionParser and override all the -difficult bits. But please don't! \module{optparse} does things the -traditional \UNIX/GNU way deliberately; the first three are -non-standard anywhere, and the last one makes sense only if you're -exclusively targeting MS-DOS/Windows and/or VMS.) +\module{optparse} does not support these option syntaxes, and it never +will. (If you really want to use one of those option syntaxes, you'll +have to subclass \class{OptionParser} and override all the difficult +bits. But please don't! \module{optparse} does things the traditional +\UNIX/GNU way deliberately; the first three are non-standard anywhere, +and the last one makes sense only if you're exclusively targeting +MS-DOS/Windows and/or VMS.) \term{option argument} an argument that follows an option, is closely associated with that @@ -150,22 +148,24 @@ Some options never take an argument. Some options always take an argument. Lots of people want an ``optional option arguments'' feature, meaning that some options will take an argument if they see it, and won't if they don't. This is somewhat controversial, because it makes -parsing ambiguous: if \programopt{-a} takes an optional argument and -\programopt{-b} is another option entirely, how do we interpret -\programopt{-ab}? \module{optparse} does not currently support this. +parsing ambiguous: if \programopt{-a} and \programopt{-b} are both +options, and \programopt{-a} takes an optional argument, how do we +interpret \programopt{-ab}? \module{optparse} does not support optional +option arguments. \term{positional argument} something leftover in the argument list after options have been -parsed, ie. after options and their arguments have been parsed and +parsed, i.e., after options and their arguments have been parsed and removed from the argument list. \term{required option} -an option that must be supplied on the command-line; the phrase -``required option'' is an oxymoron and is usually considered poor UI -design. \module{optparse} doesn't prevent you from implementing -required options, but doesn't give you much help with it either. See -``Extending Examples'' (section~\ref{optparse-extending-examples}) for -two ways to implement required options with \module{optparse}. +an option that must be supplied on the command-line. The phrase +``required option'' is an oxymoron; the presence of ``required options'' +in a program is usually a sign of careless user interface design. +\module{optparse} doesn't prevent you from implementing required +options, but doesn't give you much help with it either. See ``Extending +Examples'' (section~\ref{optparse-extending-examples}) for two ways to +implement required options with \module{optparse}. \end{definitions} @@ -177,13 +177,13 @@ For example, consider this hypothetical command-line: \programopt{-v} and \longprogramopt{report} are both options. Assuming the \longprogramopt{report} option takes one argument, -``/tmp/report.txt'' is an option argument. ``foo'' and ``bar'' are -positional arguments. +\code{/tmp/report.txt} is an option argument. \code{foo} and \code{bar} +are positional arguments. \subsubsection{What are options for?\label{optparse-options}} Options are used to provide extra information to tune or customize the -execution of a program. In case it wasn't clear, options are usually +execution of a program. In case it wasn't clear, options should be \emph{optional}. A program should be able to run just fine with no options whatsoever. (Pick a random program from the \UNIX{} or GNU toolsets. Can it run without any options at all and still make sense? |