TECO - Programming language

TECO, aka Text editor character oriented, is a programming language created in 1963.

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61Years Old

Try now: Riju

TECO (; originally an acronym for [paper] Tape editor and corrector, but later Text editor and corrector, then Text editor character oriented) is a text editor originally developed at the Massachusetts Institute of Technology (MIT) in the 1960s, after which it was modified by many other people. TECO was a direct ancestor of Emacs, which was originally implemented in TECO macros.. Read more on Wikipedia...

TECO Wikipedia page
There are 8 Project Euler users using TECO
Explore TECO snippets on Rosetta Code
TECO on HOPL
See also: (3 related languages)Emacs, Unix, ISBN

Example from Riju:

IHello, world!
$HT$$

Example from the Hello World Collection:

!Hello World in TECO
!The $ symbol below wouldn't actually be a printing character -
!it's the [escape] character, \u001b!
FTHello World$

Example from Wikipedia:

0uz                             ! clear repeat flag !
<j 0aua l                       ! load 1st char into register A !
<0aub                           ! load 1st char of next line into B !
qa-qb"g xa k -l ga -1uz '       ! if A>B, switch lines and set flag !
qbua                            ! load B into A !
l .-z;>                         ! loop back if another line in buffer !
qz;>                            ! repeat if a switch was made last pass !