From: Silas Davis <ruby@...>
Date: 2010-09-17T20:48:43+09:00
Subject: Re: Use of ? in variable names

Michael Brooks wrote:
> I'm not intending the "?" to control the parser or anything. It's just
> "decoration" to remind me that the variable or method is intended to be
> treated like a boolean when I'm looking at my code.  The "?" suffix is
> simpler than a "is_", "has_" prefix or "_flag" suffix for labeling
> booleans.  I believe one or two Ruby book even recommend that methods
> which act like booleans should end with names that have a "?".

I would also support this, and I have another case. I often use the 
idiom exemplified by:

EXTERNAL_COMMAND = lambda {|data| "command_name -abc #{data} -def"}
or
INCLUDE_RECORD = lambda {|record| (record[0] == "this") && (/.txt$/ === 
record[1])}

Where I could make the two constants full-blown methods, but I really 
like the way ruby closures allow me to separate what are essentially 
methods into a form that is both lightweight and suggestive that they 
are not first-class citizens of my business logic.

In the latter example I would really like to be able to write 
INCLUDE_RECORD? = ... In this case the naming convention would be 
exactly like that that is permitted and recommended for methods. I see 
no strong reason why this couldn't be allowed for all variable names. I 
assume currently the syntax:

bool ? <action if true> : <action if false>

Can be written:

bool? <action if true> : <action if false>

So I suppose it depends how sacred the latter case is considered. 
Personally I wouldn't mind if a space between the boolean and question 
mark was required.
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