Oldes
commented
2 years ago Mentioned LET proposal: https://github.com/Oldes/Rebol-wishes/issues/51
Open Siskin-Bot opened 4 years ago
Oldes
commented
2 years ago Mentioned LET proposal: https://github.com/Oldes/Rebol-wishes/issues/51
Submitted by: Ladislav
There have been numerous cases, when I wanted to bind a block to a context, except for some words. This can be done using some tricks, but I wonder, whether a direct addition of this feature would not be preferable?
Imported from: CureCode [ Version: alpha 110 Type: Wish Platform: All Category: Native Reproduce: Always Fixed-in:none ] Imported from: https://github.com/rebol/rebol-issues/issues/1752
Comments:
Submitted by: BrianH
In answer to the question: yes, that would help. Reworded the summary to match similar requests, changed to a wish.
The words parameter should probably take any-word! or block! of any-words, and maybe any-object! as well, and definitely none!.
Submitted by: Ladislav
I wrote this proposal before proposing the LET function. The usage of the LET function is cleaner than this, constructing the exact context. Compared to that proposal, the usage of BIND/EXCEPT does not look as a good idea.
When we start building blocks using BIND/EXCEPT, binding will become much less "reconstructible"/"redoable" than it is now, when the rule, that BIND of a block to a context is either done "completely" or not at all is not broken.
Submitted by: maxim
I've needed /except many times, especially when binding to multiple contexts.
Without except, its very complicated to manage what to bind when some words exist in both contexts.
Submitted by: BrianH
Ladislav, almost every explicit use of BIND has those same downsides - this doesn't make BIND less useful or less necessary. LET is cleaner because it has a more formalized, narrow application. A commonly needed application to be sure, so it will get a lot of use if it gets implemented, but that doesn't make BIND/except any less useful in different circumstances. It doesn't have to be a case of "either this gets accepted or that does"; both can be useful in their own way, and both can be accepted.