4 ms·

You can replace it, there are two (nearly 3) forths that replace it: https://github.com/dan4thewin/FreeForth2/blob/master/ff.asm https://github.com/dan4thewin/

You can replace it, there are two (nearly 3) forths that replace it: https://github.com/dan4thewin/FreeForth2/blob/master/ff.asm https://github.com/dan4thewin/FreeForth2/blob/master/ff.asm which uses a double loop to lookup first macro words, and then immediate words https://github.com/ablevm/able-forth/blob/current/forth.scr https://github.com/ablevm/able-forth/blob/current/forth.scr Ableforth implements a defer/expand operation \ to effectively quote words. The basic loop is then simply parse a text word, look it up and execute it. Both make use of macros (code generators) to implement deferred behaviour, as well as code inlining. Ultimately all these operations implement defer by manipulating the execution flow, something that algebraic effects also do. I have a feeling that algebraic effects can be used in a Forth to implement DOES.

retransmitfrom 1y ago
Two forths is one half.
astrobe_ 1y ago
Also Chuck Moore's ColorForth doesn't have "create does>" at all. Probably he considered the complexity was not worth it. I don't have it in my interpreter either, and I don't miss it; for the few near-misses I just use regular literals and calls. For instance, for the textbook example of "self-indexing arrays": : index-array swap cells + ; create a1 10 cells allot create a2 20 cells allot : array1 a1 index-array ; : array2 a2 index-array ; I used to use the "implementation-dependent" trick of popping the return address (in e.g. index-array) to get the data. Less verbose, a bit more efficient. But my implementation doesn't permit it anymore. Recently I've found out that implementing "self/this" pseudo-value and pseudo-method calls much more useful. The relation with this and "create does>" is that latter can be seen as poor man's closure, or poor man's object [1]. [1] https://stackoverflow.com/questions/2497801/closures-are-poor-mans-objects-and-vice-versa-what-does-this-mean https://stackoverflow.com/questions/2497801/closures-are-poo...

retransmitfrom 1y ago

Two forths is one half.

astrobe_ 1y ago

Also Chuck Moore's ColorForth doesn't have "create does>" at all. Probably he considered the complexity was not worth it. I don't have it in my interpreter either, and I don't miss it; for the few near-misses I just use regular literals and calls. For instance, for the textbook example of "self-indexing arrays": : index-array swap cells + ; create a1 10 cells allot create a2 20 cells allot : array1 a1 index-array ; : array2 a2 index-array ; I used to use the "implementation-dependent" trick of popping the return address (in e.g. index-array) to get the data. Less verbose, a bit more efficient. But my implementation doesn't permit it anymore. Recently I've found out that implementing "self/this" pseudo-value and pseudo-method calls much more useful. The relation with this and "create does>" is that latter can be seen as poor man's closure, or poor man's object [1]. [1] https://stackoverflow.com/questions/2497801/closures-are-poor-mans-objects-and-vice-versa-what-does-this-mean https://stackoverflow.com/questions/2497801/closures-are-poo...