From: Robert Klemme <shortcutter@...>
Date: 2011-03-17T17:07:47+09:00
Subject: Re: NoMethodError#message takes very long

On Wed, Mar 16, 2011 at 10:28 PM, Adiel Mittmann <adiel@inf.ufsc.br> wrote:
> Hi, I discovered what's causing the problem.
>
> Ruby's function name_err_mesg_to_str (file error.c, line 929, SVN snapshot),
> which produces the dreaded message, proceeds as follows:
>
> 1. It converts the object that does not possess the method in question to a
> string, by calling #inspect;
>
> 2. If it doesn't like that string (i.e., if it's nil or is bigger than 65
> characters), then it creates a simpler representation and use it instead.
>
> In other words, if you happen to call a method on an object that doesn't define
> to_s but that does contain a lot of data, then calling an undefined method and
> trying to print the resulting exception's message will take a long time because
> all the data in the object will have to be converted to a string -- just to be
> discarded.
>
> Maybe in a case like this the message should always return the simpler
> representation of the object instead of calling to_s?

I'd rather provide a custom #inspect method for objects which may
contain potentially large volumes of data.  Nobody can read that
anyway when printed on console or somewhere else.

Kind regards

robert

-- 
remember.guy do |as, often| as.you_can - without end
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