z (05/11/83)
The game of Life which runs under CCA EMACS has been rewritten to provide several advantages over the old version. Most importantly, it can now be run on any section of any file. All printing characters are automatically converted to astisks at the start of the game. This means that you can turn to your favorite section of your favorite file, and watch it disintegrate into strange and wondrous patterns as the game of Life progresses. Additionally, the new code is more efficient, so the game progresses faster under heavy loads. Finally, a manual page has been added for Life; here it is: EMACS Node: Life, Previous: Spell, Up: Text, Next: Dissociation Life It is possible to play the game of Life in an EMACS buffer. The buffer in which you play Life should start out with some collection of text in it; be sure that this is not your only copy of the text, as it will soon be completely destroyed. To play Life, type M-X Life<cr>. After a moment's pause, all of the printing characters on the screen will turn into asterisks, and the game is ready to begin. The rules of the game are quite simple. At the beginning of each generation, the entire screen is examined. Those asterisks which are surrounded by zero or one neighbors die away out of loneliness. Those asterisks which are surrounded by two or three neighbors are happy and stay. Those asterisks which are surrounded by four or more neighbors die away due to overcrowding. Empty spaces which are surrounded by exactly three neighbors have an asterisk born in them. Spaces are considered to be neighboring if they are adjacent either horizontally, vertically, or diagonally. At the beginning of each generation, a prompt will appear at the bottom of the screen, informing you of the generation number, the current population, and the number of births and deaths since the last generation. You will be asked if you want to continue; type 'y' to proceed to the next generation, or 'n' to quit. By holding down 'y' and the repeat key at the same time (or just 'y' if your terminal has auto-repeat), you can watch many generations flash by in a few moments. You also have the power to change the world any time you want. Temporarily exit from the game by typing 'n' to the prompt. Then, simply edit the picture by inserting and deleting asterisks where you like. (EMACS makes this simple by leaving you in Overwrite mode.) Finally, resume the game by typing M-X Life again.