# Author: Fred L. Drake, Jr. # fdrake@cnri.reston.va.us, fdrake@acm.org # # This is a simple little module I wrote to make life easier. I didn't # see anything quite like it in the library, though I may have overlooked # something. I wrote this when I was trying to read some heavily nested # tuples with fairly non-descriptive content. This is modelled very much # after Lisp/Scheme - style pretty-printing of lists. If you find it # useful, thank small children who sleep at night. """Support to pretty-print lists, tuples, & dictionaries recursively. Very simple, but useful, especially in debugging data structures. Classes ------- PrettyPrinter() Handle pretty-printing operations onto a stream using a configured set of formatting parameters. Functions --------- pformat() Format a Python object into a pretty-printed representation. pprint() Pretty-print a Python object to a stream [default is sys.sydout]. saferepr() Generate a 'standard' repr()-like value, but protect against recursive data structures. """ from types import DictType, ListType, TupleType try: from cStringIO import StringIO except ImportError: from StringIO import StringIO def pprint(object, stream=None): """Pretty-print a Python object to a stream [default is sys.sydout].""" printer = PrettyPrinter(stream=stream) printer.pprint(object) def pformat(object): """Format a Python object into a pretty-printed representation.""" return PrettyPrinter().pformat(object) def saferepr(object): """Version of repr() which can handle recursive data structures.""" return _safe_repr(object, {}) class PrettyPrinter: def __init__(self, indent=1, width=80, depth=None, stream=None): """Handle pretty printing operations onto a stream using a set of configured parameters. indent Number of spaces to indent for each level of nesting. width Attempted maximum number of columns in the output. depth The maximum depth to print out nested structures. stream The desired output stream. If omitted (or false), the standard output stream available at construction will be used. """ assert (not depth) or depth > 0, "depth may not be negative" assert int(indent) or 1 assert int(width) or 1 self.__depth = depth self.__indent_per_level = indent self.__width = width if stream: self.__stream = stream else: import sys self.__stream = sys.stdout def pprint(self, object): self.__stream.write(self.pformat(object) + "\n") def pformat(self, object): sio = StringIO() self.__format(object, sio, 0, 0, {}, 0) return sio.getvalue() def __format(self, object, stream, indent, allowance, context, level): level = level + 1 if context.has_key(id(object)): object = _Recursion(object) rep = self.__repr(object, context, level - 1) objid = id(object) context[objid] = 1 typ = type(object) sepLines = len(rep) > (self.__width - 1 - indent - allowance) if sepLines and typ in (ListType, TupleType): # Pretty-print the sequence. stream.write((typ is ListType) and '[' or '(') length = len(object) if length: indent = indent + self.__indent_per_level self.__format(object[0], stream, indent, allowance + 1, context, level) if len(object) > 1: for ent in object[1:]: stream.write(',\n' + ' '*indent) self.__format(ent, stream, indent, allowance + 1, context, level) indent = indent - self.__indent_per_level stream.write(((typ is ListType) and ']') or ')') elif sepLines and typ is DictType: stream.write('{') length = len(object) if length: indent = indent + self.__indent_per_level items = object.items() items.sort() key, ent = items[0] rep = self.__repr(key, context, level) + ': ' stream.write(rep) self.__format(ent, stream, indent + len(rep), allowance + 1, context, level) if len(items) > 1: for key, ent in items[1:]: rep = self.__repr(key, context, level) + ': ' stream.write(',\n' + ' '*indent + rep) self.__format(ent, stream, indent + len(rep), allowance + 1, context, level) indent = indent - self.__indent_per_level stream.write('}') else: stream.write(rep) del context[objid] def __repr(self, object, context, level): return _safe_repr(object, context, self.__depth, level) def _safe_repr(object, context, maxlevels=None, level=0): level = level + 1 typ = type(object) if not (typ in (DictType, ListType, TupleType) and object): return `object` if context.has_key(id(object)): return `_Recursion(object)` objid = id(object) context[objid] = 1 if typ is DictType: if maxlevels and level >= maxlevels: s = "{...}" else: items = object.items() k, v = items[0] s = "{%s: %s" % (_safe_repr(k, context, maxlevels, level), _safe_repr(v, context, maxlevels, level)) for k, v in items[1:]: s = "%s, %s: %s" \ % (s, _safe_repr(k, context, maxlevels, level), _safe_repr(v, context, maxlevels, level)) s = s + "}" else: s, term = (typ is ListType) and ('[', ']') or ('(', ')') if maxlevels and level >= maxlevels: s = s + "..." else: s = s + _safe_repr(object[0], context, maxlevels, level) for ent in object[1:]: s = "%s, %s" % (s, _safe_repr(ent, context, maxlevels, level)) s = s + term del context[objid] return s class _Recursion: # represent a recursive relationship; really only used for the __repr__() # method... def __init__(self, object): self.__repr = "" \ % (type(object).__name__, id(object)) def __repr__(self): return self.__repr 36441ed59 Tcl is a high-level, general-purpose, interpreted, dynamic programming language. It was designed with the goal of being very simple but powerful.
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* * generic/tclExecute.c: Corrected flawed overflow detection indgp2006-07-263-3/+16
* * win/tclWinSock.c: Correct un-initialized Tcl_DString. Thanksdgp2006-07-242-15/+23
* undo mistaken commitdgp2006-07-212-20/+17
* * generic/tclExecute.c:Miguel Sofer2006-07-215-22/+48
* typosdas2006-07-211-3/+3
* cleanup quoting and whitespacedas2006-07-202-5/+6
* * macosx/tclMacOSXNotify.c (Tcl_InitNotifier, Tcl_WaitForEvent): createdas2006-07-2013-1009/+1419
* * generic/regc_locale.c (cclass):das2006-07-209-50/+51
* * unix/tclUnixPort.h: Added the inclusion ofandreas_kupries2006-07-142-1/+13
* Made Tcl_AsyncDelete() more tolerant when called after all thread TSDvasiljevic2006-07-11