vault backup: 2025-03-24 23:50:46

Minecraft Datapacking/When Two Macros are Faster than One.md

@@ -34,13 +34,32 @@ function searchArray(keyword: string) {
 
 searchArray('entry500')
 ```
-In mcfunction, this is not so easy. We *could* use macros
+In mcfunction, this is not so straightforward. Macros would make this really clean:
+```vb
+function test_namespace:search_array {keyword: "entry500"}
+```
+Unfortunately, macros come with a performance hit. A more performant method, albeit less elegant, is to store the keyword in NBT storage prior to calling the function. The storage can be removed after the function is run:
+```vb
+data modify storage test_namespace:test_namespace temp.keyword set value 'entry500'
+function test_namespace:search_array
+data remove storage test_namespace:test_namespace temp.keyword
+
+```
+Once the entry is found, it is stored in the `temp.result` storage, which can then be consumed by another function.
+
+Now for the logic to do the actual array searching...
 # one macro
-Macros allow us to reach into our array and pick out an entry that matching value in the `string` property.
+Macros allow us to reach into our array and pick out an entry that matching value in the `string` property. This is something that I didn't realize (for some reason) and was pointed out by **PuckiSilver** and **amandin** on the Datapack Hub discord server.
 ```vb
 ... one_macro.array[string:$(keyword)]
 ```
+This method is super clean and results in a one liner that is wordy but simple:
+```vb
+'# one_macro/_searcharray.mcfunction
 
+$data modify storage test_namespace:test_namespace temp.result set from storage test_namespace:test_namespace one_macro.array[string:$(keyword)]
+```
+`_searcharray` can then be called using the `temp.keyword` storage:
 ```vb
 '# one_macro/run.mcfunction
 
@@ -49,15 +68,37 @@ data modify storage test_namespace:test_namespace temp.keyword set value 'entry5
 function test_namespace:one_macro/_searcharray with storage test_namespace:test_namespace temp
 
 data remove storage test_namespace:test_namespace temp.keyword
+
+'# call the function that consumes 'temp.result', then remove it
 data remove storage test_namespace:test_namespace temp.result
 ```
-
-```vb
-'# one_macro/_searcharray.mcfunction
-
-$data modify storage test_namespace:test_namespace temp.result set from storage test_namespace:test_namespace one_macro.array[string:$(keyword)]
-```
 # two macro
+Another way to crack the problem is through indexing. This was my original plan when I didn't realize that `...[string:$(keyword)]` was possible.
+
+This method requires the creation of an index of the field that is going to be searched. The index will look something like this:
+```json
+[
+	{entry1: 0},
+	{entry2: 1},
+	...
+	{entry500: 499}
+]
+```
+The *key*, e.g. `entry2:` corresponds with the value of a `string` field in the main array, while the value `1` indicates the main array index where we'll find the full entry. The index can be searched with a direct path, `index.$(keyword)`, and the main array can also be searched with a direct reference to the entry index, `array.#(index)`. Keep in mind that *the index must already exist prior to running the search function*. In a practical application, an index could be updated every time the main array is updated. A scheduled task could also audit the index to ensure that it's up to date.
+
+The index search looks like this:
+```vb
+'# two_macro/_searchindex.mcfunction
+
+$data modify storage test_namespace:test_namespace temp.index set from storage test_namespace:test_namespace two_macro.index.$(keyword)
+```
+And the array search looks like this:
+```vb
+'# two_macro/_searcharray.mcfunction
+
+$data modify storage test_namespace:test_namespace temp.result set from storage test_namespace:test_namespace two_macro.array[$(index)]
+```
+The index and array search functions are then called using the `temp.keyword` storage:
 ```vb
 '# two_macro/run.mcfunction
 
@@ -69,17 +110,8 @@ function test_namespace:two_macro/_searcharray with storage test_namespace:test_
 
 data remove storage test_namespace:test_namespace temp.keyword
 data remove storage test_namespace:test_namespace temp.index
+
+'# call the function that consumes 'temp.result', then remove it
 data remove storage test_namespace:test_namespace temp.result
 ```
 
-```vb
-'# two_macro/_searchindex.mcfunction
-
-$data modify storage test_namespace:test_namespace temp.index set from storage test_namespace:test_namespace two_macro.index.$(keyword)
-```
-
-```vb
-'# two_macro/_searcharray.mcfunction
-
-$data modify storage test_namespace:test_namespace temp.result set from storage test_namespace:test_namespace two_macro.array[$(index)]
-```