[TheForge] using tools to build tools

[Andrew Vida]

Paul N wrote:

> The first computers were designed by hand with pencil an paper, hand 
> soldered and assembled. Eventually the computers were adequate to do be 
> used for the calculations and design process, later being relegated more 
> specialized tasks such chip design, verification, and even assembly. 
> Same for the programs. There weren't always programs like compilers and 
> debuggers. A lot of "coding" was done by hand, even into the 70's.

	Writing a compiler completely by hand is a mind numbingly complex task. 
  I know because I've done several of them, and even those were not 
completely coded by hand, but rather using tools like lex and yacc, 
which makes the job an order of magnitude simpler.  While scanners are 
not that terribly difficult to write from scratch, parsers are.  The 
advent of tools like yacc changed the world - literally.