René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Autocompletion on rcParams: long-overdue restructuring of rcParams","articleBody":"It would be great to have autocompletion on `rcParams` (or `settings`) in IPython, so you could do\n\n```\nsettings[\"fon\u003cTAB\u003e\"]\n```\n\nand get a list of all keys containing the string \"fon\".\nThis would be another tool to get people modifying settings.\n\nCurrently there is no completion on dictionary keys in IPython -- I am hoping to implement this this week.\n\nHowever, a nicer solution, in my opinion, is attribute access, so you could do e.g.\n\n```\nsettings.xtick.color = 'b'\n```\n\nThis is easy to implement by hand. But it turns out that it is already implemented in IPython! Even if in a slightly obscure (but super-general so nothing done by hand) way:\n\n```\nfrom matplotlib import rcParams\nfrom IPython.config import Config\n\nsettings = Config(rcParams)\n```\n\nYou can now _automatically_  use the `settings.xtick.color` syntax _and_ completion!:\n\n```\nsettings.xtic\u003cTAB\u003e\n```\n\ngives a list of all the settings starting with `xtic`. (See below for more completion magic).\n\n_However_, there is a problem with the names of the `rcParams` keys using `.` as a separator, namely that doing\n\n```\nsettings.xtick.\u003cTAB\u003e\n```\n\nno longer completes anything. This is because it is treating `settings.xtick` as a subdictionary or subclass.\n\nThere are 2 possible solutions:\n1. Change the names of the `settings` keys, e.g. to xtick_minor_pad. Yuck.\n2. An excellent solution -- not just for this autocompletion problem -- is the following:\n\nReally turn the sequence of names including `.`s in the string in the attribute-access pattern into _real sub-dictionaries_  of `rcParams`.\n\nOf course, this makes the dictionary key syntax horrible, but there would be no longer be any need for it -- we would just switch over wholesale to the `.` attribute syntax.\n\nOf course, this breaks some backward compatibility, but it gives a much more logical structure to rcParams as a whole.\n[And, thinking about it, it should be possible to rewrite the dictionary access functions so that the old key accesses still work!]\n\nOf course, the magic going on in the IPython.config module is easily extractable straight in to rcParams, in case somebody is worried that this depends on IPython.\n\n------- [Comments on future IPython command completion possibilities below]\n\nIn fact, I have a mod for IPython's command completion which completes any word containing the letters that you type in a certain order. Here is the output for\n\n```\nsettings.fon\u003cTAB\u003e:\n```\n\n```\nsettings.figure.frameon           settings.legend.fontsize\nsettings.figure.max_open_warning  settings.legend.frameon\nsettings.font.cursive             settings.mathtext.fontset\nsettings.font.family              settings.pdf.compression\nsettings.font.fantasy             settings.pdf.fonttype\nsettings.font.monospace           settings.pdf.use14corefonts\nsettings.font.sans-serif          settings.pgf.rcfonts\nsettings.font.serif               settings.ps.fonttype\nsettings.font.size                settings.savefig.extension\nsettings.font.stretch             settings.savefig.frameon\nsettings.font.style               settings.savefig.orientation\nsettings.font.variant             settings.svg.fonttype\nsettings.font.weight              \n```\n\nIt includes things that don't _start_  with `fon` but contain the sequence of characters `f`, `o`, `n` in that order.\n\nAn alternative is to just search for the word `fon`, without splitting up the characters.\nI hope to submit an IPython pull request soon. It will be possible to change between these different types of completion mechanism with a standard IPython configuration method.\n","author":{"url":"https://github.com/dpsanders","@type":"Person","name":"dpsanders"},"datePublished":"2013-07-24T13:08:34.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/2249/matplotlib/issues/2249"}