eric4.DebugClients.Python.FlexCompleter

Word completion for the eric4 shell

NOTE for eric4 variant

This version is a re-implementation of FlexCompleter as found in the PyQwt package. It is modified to work with the eric4 debug clients.

NOTE for the PyQwt variant

This version is a re-implementation of FlexCompleter with readline support for PyQt&sip-3.6 and earlier.

Full readline support is present in PyQt&sip-snapshot-20030531 and later.

NOTE for FlexCompleter

This version is a re-implementation of rlcompleter with selectable namespace.

The problem with rlcompleter is that it's hardwired to work with __main__.__dict__, and in some cases one may have 'sandboxed' namespaces. So this class is a ripoff of rlcompleter, with the namespace to work in as an optional parameter.

This class can be used just like rlcompleter, but the Completer class now has a constructor with the optional 'namespace' parameter.

A patch has been submitted to Python@sourceforge for these changes to go in the standard Python distribution.

Original rlcompleter documentation

This requires the latest extension to the readline module (the completes keywords, built-ins and globals in __main__; when completing NAME.NAME..., it evaluates (!) the expression up to the last dot and completes its attributes.

It's very cool to do "import string" type "string.", hit the completion key (twice), and see the list of names defined by the string module!

Tip: to use the tab key as the completion key, call

'readline.parse_and_bind("tab: complete")'

Notes:

Exceptions raised by the completer function are *ignored* (and generally cause the completion to fail). This is a feature -- since readline sets the tty device in raw (or cbreak) mode, printing a traceback wouldn't work well without some complicated hoopla to save, reset and restore the tty state.
The evaluation of the NAME.NAME... form may cause arbitrary application defined code to be executed if an object with a __getattr__ hook is found. Since it is the responsibility of the application (or the user) to enable this feature, I consider this an acceptable risk. More complicated expressions (e.g. function calls or indexing operations) are *not* evaluated.
GNU readline is also used by the built-in functions input() and raw_input(), and thus these also benefit/suffer from the completer features. Clearly an interactive application can benefit by specifying its own completer function and using raw_input() for all its input.
When the original stdin is not a tty device, GNU readline is never used, and this module (and the readline module) are silently inactive.

Global Attributes

__all__

Classes

Completer

Class implementing the command line completer object.

Functions

get_class_members

Module function to retrieve the class members.

Completer

Class implementing the command line completer object.

Derived from

object

Class Attributes

None

Class Methods

None

Methods

Completer	Create a new completer for the command line.
attr_matches	Compute matches when text contains a dot.
complete	Return the next possible completion for 'text'.
global_matches	Compute matches when text is a simple name.

Static Methods

None

Completer (Constructor)

Completer(namespace = None)

Create a new completer for the command line.

Completer([namespace]) -> completer instance.

If unspecified, the default namespace where completions are performed is __main__ (technically, __main__.__dict__). Namespaces should be given as dictionaries.

Completer instances should be used as the completion mechanism of readline via the set_completer() call:

readline.set_completer(Completer(my_namespace).complete)

namespace: The namespace for the completer.

Completer.attr_matches

attr_matches(text)

Compute matches when text contains a dot.

Assuming the text is of the form NAME.NAME....[NAME], and is evaluatable in self.namespace, it will be evaluated and its attributes (as revealed by dir()) are used as possible completions. (For class instances, class members are are also considered.)

WARNING: this can still invoke arbitrary C code, if an object with a __getattr__ hook is evaluated.

text: The text to be completed. (string)

Returns:: A list of all matches.

Completer.complete

complete(text, state)

Return the next possible completion for 'text'.

This is called successively with state == 0, 1, 2, ... until it returns None. The completion should begin with 'text'.

text: The text to be completed. (string)
state: The state of the completion. (integer)

Returns:: The possible completions as a list of strings.

Completer.global_matches

global_matches(text)

Compute matches when text is a simple name.

text: The text to be completed. (string)

Returns:: A list of all keywords, built-in functions and names currently defined in self.namespace that match.

get_class_members

get_class_members(klass)

Module function to retrieve the class members.

klass: The class object to be analysed.

Returns:: A list of all names defined in the class.