From: Eric Hodel <drbrain@...7.net>
Date: 2005-03-30T15:29:09+09:00
Subject: Re: Open letter to anyone developing a Ruby IDE

On 29 Mar 2005, at 21:30, Lothar Scholz wrote:

> Hello Eric,
>
>
> EH> Where exactly does type inference come in for an auto-completion
> EH> feature for an IDE?
>
> EH> Something so heavyweight as type inferencing is unnecessary for 
> doing
> EH> 90% of the work of figuring out what the likely completions for a
> EH> particular chunk of code you're writing.
>
> EH> While this won't get an accurate completion every time, you really
> EH> don't care.  You'll find that 90% of the time the word you want is 
> less
> EH> than 3 presses of tab away.
>
> Unfortunately this is not what people expect, at least when they come
> from the Java world. Code Completition is a learning tool not
> primarily to save some keystrokes. You slowly learn the available
> messages for a class while writing your code. Therefore a much better
> way then showing a huge list with hundrets of strings list should be
> available.

Have you used Readline tab completion in irb?  It is far from useful, 
giving you too many potential completions from too far up the 
inheritance tree.

> And methods have the heuristic that they share a common
> prefix and differ only the last characters. This makes your
> (emacs/vi) completition even more useless.

In the cases where I've found methods that share a common prefix, I've 
found it rare that I'm actually calling those methods from regular 
code.  Test::Unit is the best example of this.  I have many, many 
methods starting with test_ but I never call them.

In the cases in Ruby where there are methods that share a common 
prefix, #each comes to mind, I don't see how this is useless at all.

I type ea<tab> and see "each" then I hit tab again "each_line" and 
again "each_with_index" which is the one I wanted.  I don't see how 
that's less useful than the ones I've seen in MS' VB editors.  
(Besides, I'd never tab-complete 'each', all but the 'c' is on the home 
row of a Dvorak keyboard.)

If you still think its totally useless I'd like to see a series of 
keystrokes that show how it falls down.

FWIW, ri says there's the following possible each completions:
Core: #each #each_line, #each_with_index, #each_value, #each_pair, 
#each_key, #each_byte, #each_object, #each_pair
Pathname: #each_entry, #each_filename
YAML: #each_document, #each_node
Vector: #each2

You can only get those last 5 by requiring extra libraries.

-- 
Eric Hodel - drbrain@segment7.net - http://segment7.net
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