This is a constant so you cannot just assign it a dynamic value.

If you really want, you can assign it an instance of a class that
exposes an interface similar to that of a Hash but acts dynamically.

You'd still need to somehow get the value of "%i", whatever that is
(I'm not familiar with IRB configuration but I know it's very hard to
achieve this with Ruby so I just guess you meant @i or something (if
I'm wrong, sorry)).

You might as well just modify a few lines of IRB code, I guess.

By the way, printf() like formatitng in Ruby has a great syntax:

"%f" % 0.1
"%d %d" % [1, 2]

(String could be dynamic, Numerics could be dynamic, Array could be dynamic).


Have a look at the  Adopt-a-newbie thread here in the mailing list :-)


Aur Saraf

On 2/17/07, Peter B. <peter.bunyan / googlemail.com> wrote:
> Hi, I'm new to this newsgroup, so I'm not sure if this is the right
> place to ask.
>
> Ok, so what I'm trying to do is customise the IRB prompt in a rather
> complicated way: I want to print %i*2 (or even just %i) spaces at the
> beginning of each line of prompt. Here was my best attempt (not sure
> if there's a better way to format this for Usenet):
>
> IRB.conf[:PROMPT][:INDENTS] = {
>   :PROMPT_I => "#{%i.times {print '  '}} >> ",
>   :PROMPT_S => "#{%i.times {print '  '}} >> ",
>   :PROMPT_C => "#{%i.times {print '  '}} >> ",
>   :RETURN => "=> %s\n"
> }
>
> So, what I want it do is like this:
>
>  >> if "Jim" == "Fred"
>    >> print "Ruby Sucks!"
>    >> else
>    >> print "Ruby is cool!"
>    >> end
>  >> print "And you know it!"
>
> But obviously, It tries to work out the value of the #{ } as soon as
> it's set, not when it's displayed, after the %i has been gsub'd for
> displaying. So, I get an error thrown at me.
>
> Does anybody know how to do this? Maybe some printf() trickery?
>
> Thanks in advance.
>
>
>