From: itsme213 <itsme213@...>
Date: 2005-09-16T04:36:38+09:00
Subject: Re: Appropriate use of "inject()" ?

Ah, I need to think more "functional programming".

Thanks a bunch, all. Useful general lesson for me.

"Martin DeMello" <martindemello@yahoo.com> wrote in message
news:3BjWe.204172$Hk.56955@pd7tw1no...
> itsme213 <itsme213@hotmail.com> wrote:
> > I have a hash table HASH containing strings, and want to generate a
string
> > for an equivalent Javascript variable JS from it e.g.
> >
> > HASH = {'a' => 'A', 'b' => 'B'}
> >
> > "var JS = { 'a' : 'A', 'b' : 'B' }"
> >
> > I thought inject was just the ticket:
> >
> > 'var JS = {' +
> >   HASH.inject("") { |str, kv| str << "\n\t'#{kv[0]}' : #{kv[1]}, " } +
> >   "};"
> >
> > But this puts a "," after the last item. Is there a simple alternative?
>
> The simplest is the two-pass
>
> 'var JS = {' + HASH.map {|k,v| "'#{k}' : '#{v}'"}.join(",\n\t") +  "};"
>
> #join has extra logic to specialcase the last element, which is painful
> with #inject.
>
> martin