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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.forth
Subject: Re: Stack Operator Symbols
Date: Sat, 29 Oct 2016 00:46:20 -0700
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"Elizabeth D. Rather" <erather@forth.com> writes:
> I wrote Forth professionally for 30 years without using PICK, ROLL, or
> -ROLL, suffering zero inconvenience.

I needed a 3DUP word recently, and wrote something like:

   : 3dup ( a b c -- a b c a b c ) >r 2dup r@ -rot r> ;

Later I saw someone else's implementation:

   : 3dup ( a b c -- a b c a b c ) 2 pick 2 pick 2 pick ;

which I thought was much more symmetric and natural.  Of course for
non-purists,

   : 3dup { a b c } a b c a b c ;

is the simplest of all.