FIND/in - a pattern I use a lot
I often store records as blocks. The blocks follow a standard format. For example, if you look at the R3 chat message file, you will see such a format.
So, this common code pattern appears a lot. I often use it for finding a user in a user database:
foreach user users [ ; or similar FORALL loop
if user/3 = name [return user]
You will recognize this as a linear search. I use it in cases where its not worth building a hash (map!) on the target field, normally because it's rarely needed, or the database is small.
It's time to abstract this type of search. The key elements are:
- Search block of blocks
- A specific field of each
- That equals a given value
So, it could be something like:
user: find/in users 3 name
And user is probably the index into the users block, allowing us to do things like:
remove find/in users 3 name
The method could be extended to blocks of objects:
rec: find/in objects word value
The same as:
foreach obj objects [ ; or similar FORALL loop
if obj/:word = value [return obj]
This is one of those cases where you begin to ask, is this more of a native or a mezzanine function?
Of course, another approach would be to add a function that is a bit similar to an SQL select, but it's also more work, and I'm not sure how much use it would get.
Let me know your thoughts.