faif-2.0

after the two-key combination that triggered it. Mikkelson’s hack
switched TECO from its usual abstract command-execution mode to a
more intuitive keystroke-by-keystroke mode. The only flaws were that
it used just five lines of the screen and was too inefficient for real use.
Stallman reimplemented the feature to use the whole screen efficiently,
then extended it in a subtle but significant way. He made it possible to
attach TECO command strings, or “macros,” to keystrokes. Advanced
TECO users already saved macros in files; Stallman’s hack made it possible
to call them up fast. The result was a user-programmable WYSI-
WYG editor. “That was the real breakthrough,” says Guy Steele, a
fellow AI Lab hacker at the time. 7
By Stallman’s own recollection, the macro hack touched off an explosion
of further innovation. “Everybody and his brother was writing
his own collection of redefined screen-editor commands, a command for
everything he typically liked to do,” Stallman would later recall. “People
would pass them around and improve them, making them more
powerful and more general. The collections of redefinitions gradually
became system programs in their own right.” 8
So many people found the macro innovations useful and had incorporated
it into their own TECO programs that the TECO editor
had become secondary to the macro mania it inspired. “We started
to categorize it mentally as a programming language rather than as
an editor,” Stallman says. Users were experiencing their own pleasure
tweaking the software and trading new ideas. 9
Two years after the explosion, the rate of innovation began to
exhibit inconvenient side effects. The explosive growth had provided
an exciting validation of the collaborative hacker approach, but it had
also led to incompatibility. “We had a Tower of Babel effect,” says
Guy Steele.
The effect threatened to kill the spirit that had created it, Steele
says. Hackers had designed ITS to facilitate programmers’ ability to
share knowledge and improve each other’s work. That meant being
able to sit down at another programmer’s desk, open up a programmer’s
work and make comments and modifications directly within the
software. “Sometimes the easiest way to show somebody how to program
or debug something was simply to sit down at the terminal and
do it for them,” explains Steele.
83