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Editing: pipes.cpython-33.pyc
� �� f�" c @ s� d Z d d l Z d d l Z d d l Z d d l m Z d g Z d Z d Z d Z d Z d Z d Z e e e e e e g Z Gd d � d � Z d d � Z d S( u� Conversion pipeline templates. The problem: ------------ Suppose you have some data that you want to convert to another format, such as from GIF image format to PPM image format. Maybe the conversion involves several steps (e.g. piping it through compress or uuencode). Some of the conversion steps may require that their input is a disk file, others may be able to read standard input; similar for their output. The input to the entire conversion may also be read from a disk file or from an open file, and similar for its output. The module lets you construct a pipeline template by sticking one or more conversion steps together. It will take care of creating and removing temporary files if they are necessary to hold intermediate data. You can then use the template to do conversions from many different sources to many different destinations. The temporary file names used are different each time the template is used. The templates are objects so you can create templates for many different conversion steps and store them in a dictionary, for instance. Directions: ----------- To create a template: t = Template() To add a conversion step to a template: t.append(command, kind) where kind is a string of two characters: the first is '-' if the command reads its standard input or 'f' if it requires a file; the second likewise for the output. The command must be valid /bin/sh syntax. If input or output files are required, they are passed as $IN and $OUT; otherwise, it must be possible to use the command in a pipeline. To add a conversion step at the beginning: t.prepend(command, kind) To convert a file to another file using a template: sts = t.copy(infile, outfile) If infile or outfile are the empty string, standard input is read or standard output is written, respectively. The return value is the exit status of the conversion pipeline. To open a file for reading or writing through a conversion pipeline: fp = t.open(file, mode) where mode is 'r' to read the file, or 'w' to write it -- just like for the built-in function open() or for os.popen(). To create a new template object initialized to a given one: t2 = t.clone() i N( u quoteu Templateu ffu -fu f-u --u .-u -.c B s� | Ee Z d Z d Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d S( u Templateu' Class representing a pipeline template.c C s d | _ | j � d S( u- Template() returns a fresh pipeline template.i N( u debuggingu reset( u self( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu __init__U s u Template.__init__c C s d | j f S( u t.__repr__() implements repr(t).u <Template instance, steps=%r>( u steps( u self( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu __repr__Z s u Template.__repr__c C s g | _ d S( u< t.reset() restores a pipeline template to its initial state.N( u steps( u self( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu reset^ s u Template.resetc C s/ t � } | j d d � | _ | j | _ | S( ub t.clone() returns a new pipeline template with identical initial state as the current one.N( u Templateu stepsu debugging( u selfu t( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu cloneb s u Template.clonec C s | | _ d S( u( t.debug(flag) turns debugging on or off.N( u debugging( u selfu flag( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu debugj s u Template.debugc C s t | � t d � k r' t d � � n | t k rI t d | f � � n | t k rd t d � � n | j r� | j d d t k r� t d � � n | d d k r� t j d | � r� t d � � n | d d k r� t j d | � r� t d � � n | j j | | f � d S( u/ t.append(cmd, kind) adds a new step at the end.u u% Template.append: cmd must be a stringu Template.append: bad kind %ru- Template.append: SOURCE can only be prependedi u' Template.append: already ends with SINKi u fu \$IN\bu# Template.append: missing $IN in cmdu \$OUT\bu$ Template.append: missing $OUT in cmdNi����( u typeu TypeErroru stepkindsu ValueErroru SOURCEu stepsu SINKu reu searchu append( u selfu cmdu kind( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu appendn s ##u Template.appendc C s t | � t d � k r' t d � � n | t k rI t d | f � � n | t k rd t d � � n | j r� | j d d t k r� t d � � n | d d k r� t j d | � r� t d � � n | d d k r� t j d | � r� t d � � n | j j d | | f � d S( u2 t.prepend(cmd, kind) adds a new step at the front.u u& Template.prepend: cmd must be a stringu Template.prepend: bad kind %ru+ Template.prepend: SINK can only be appendedi i u, Template.prepend: already begins with SOURCEu fu \$IN\bu$ Template.prepend: missing $IN in cmdu \$OUT\bu% Template.prepend: missing $OUT in cmdN( u typeu TypeErroru stepkindsu ValueErroru SINKu stepsu SOURCEu reu searchu insert( u selfu cmdu kind( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu prepend~ s ##u Template.prependc C sI | d k r | j | � S| d k r2 | j | � St d | f � � d S( u~ t.open(file, rw) returns a pipe or file object open for reading or writing; the file is the other end of the pipeline.u ru wu, Template.open: rw must be 'r' or 'w', not %rN( u open_ru open_wu ValueError( u selfu fileu rw( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu open� s u Template.openc C s^ | j s t | d � S| j d d t k r< t d � � n | j | d � } t j | d � S( ui t.open_r(file) and t.open_w(file) implement t.open(file, 'r') and t.open(file, 'w') respectively.u ri u) Template.open_r: pipeline ends width SINKu i����( u stepsu openu SINKu ValueErroru makepipelineu osu popen( u selfu fileu cmd( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu open_r� s u Template.open_rc C s^ | j s t | d � S| j d d t k r< t d � � n | j d | � } t j | d � S( Nu wi i u, Template.open_w: pipeline begins with SOURCEu ( u stepsu openu SOURCEu ValueErroru makepipelineu osu popen( u selfu fileu cmd( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu open_w� s u Template.open_wc C s t j | j | | � � S( N( u osu systemu makepipeline( u selfu infileu outfile( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu copy� s u Template.copyc C s9 t | | j | � } | j r5 t | � d | } n | S( Nu set -x; ( u makepipelineu stepsu debuggingu print( u selfu infileu outfileu cmd( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu makepipeline� s u Template.makepipelineN( u __name__u __module__u __qualname__u __doc__u __init__u __repr__u resetu cloneu debugu appendu prependu openu open_ru open_wu copyu makepipeline( u __locals__( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu TemplateR s c C s� g } x- | D]% \ } } | j d | | d g � q W| sX | j d d d d g � n | d d d � \ } } | d d k r� | r� | j d d d d d g � n | | d d <| d d d � \ } } | d d k r| r| j d d d d g � n | | d d <g } x� t d t | � � D]� } | | d d } | | d } | d d k ss| d d k r-t j � \ } } t j | � | j | � | | | d d <| | d <q-q-Wx� | D]� } | \ } } } } | d d k rd t | � d | } n | d d k r9d t | � d | } n | d d k rf| rf| d t | � } n | d d k r�| r�| d t | � } n | | d <q�W| d d } xz | d d � D]h } | d d � \ } } | d d k rd | k r d | d } n | d | } q�| d | } q�W| r�d } x" | D] } | d t | � } q?Wd t | d � d } | d | d | } n | S( Nu u catu --i i i u fi u OUT=u ; u IN=u -u <u >u { u ; }u | u u rm -fu u trap u ; exitu 1 2 3 13 14 15i����i����i����i����( u appendu insertu rangeu lenu tempfileu mkstempu osu closeu quote( u infileu stepsu outfileu listu cmdu kindu garbageu iu lkindu rkindu fdu tempu itemu infu outfu cmdlistu rmcmdu fileu trapcmd( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu makepipeline� s` % u makepipeline( u __doc__u reu osu tempfileu shlexu quoteu __all__u FILEIN_FILEOUTu STDIN_FILEOUTu FILEIN_STDOUTu STDIN_STDOUTu SOURCEu SINKu stepkindsu Templateu makepipeline( ( ( u* /opt/alt/python33/lib64/python3.3/pipes.pyu <module>9 s c
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