Adapter

2026-08-26T14:17:19Z

GHXX: Created page with "Adapter block This block allows you to interact with non Advanced Computers blocks, such as the vanilla Minecraft jukebox, or blocks from other addon mods. It also offers special functionality for interacting with another Computer. The provided functionality changes based on the block that it is facing. == Provided component == This block provides the <code>adapter</code> component, offering the following propert..."

File:Adapter block.png

2026-08-26T14:03:55Z

GHXX:

2026-08-25T15:53:20Z

GHXX:

{{Template:Future Content}}Description

== Provided component ==
This block provides the <code>digitalCrafter</code> component, offering the following properties:
{| class="wikitable"
|+DigitalCrafterUD component properties
!Name
!Type
!Read/Write
!Description
|-
|<code>cooldownRemaining</code>
|<code>number</code>
|READ
|How much more time needs to pass before <code>:craft</code> may be called again.
|}
{| class="wikitable"
|+DigitalCrafterUD component methods
!Name
!Type
!Description
|-
| style="white-space: nowrap;" |<code>:searchRecipesWithIngredient(ingredient:string)</code>
|<code>recipe[]</code>
|Returns all crafting recipes that use <code>ingredient</code> as an input. The ingredient needs to be in the format <code>modname:itemname</code>, e.g. <code>minecraft:stick</code>.
The result is a table of recipes, where each recipe is again a table that looks like the following:<syntaxhighlight lang="lua">{
ingredients={
{"minecraft:coal","minecraft:charcoal"}, nil, nil,
{"minecraft:stick"}, nil, nil,
nil,nil,nil
},
result="minecraft:torch",
resultCount=4
}</syntaxhighlight>The <code>ingredients</code> entry represents a 3x3 grid, left to right, top to bottom.
|-
| style="white-space: nowrap;" |<code>:searchRecipesWithResult(result:string)</code>
|<code>recipe[]</code>
|Returns all crafting recipes that produce the given item.
|-
| style="white-space: nowrap;" |<code>:searchItemByName(string:partialName)</code>
|<code>string</code>
|Returns all item names matching the given query string.
|-
|<code><nowiki>:craft(ingredients:(string|nil)[], resultItem:string, int:amount, boolean:outputIntoOwnInventory)</nowiki></code>
|<code>integer</code>
|If all required items are available, crafts the result. If <code>outputIntoOwnInventory</code> is <code>true</code> the result is put into the own inventory. Otherwise it is pushed into the inventory that may be above, or it is ejected above in-world. '''Beware that there is no destination check to make sure that there is room in the inventory above, so items may spill if the destination is full.'''
Ingredients are supplied as a table of entries, similar to the ingredients field in recipes, but with a fixed value instead of a table in each slot. E.g. The recipe above can be supplied as <code>{"minecraft:coal", nil, nil, "minecraft:stick"}</code>. The parameter <code>amount</code> refers to how often this recipe should be crafted. So applying this recipe 3 times and crafting <code>minecraft:torch</code> will try to produce 12 items.

Due to the possibility of <code>recipe.resultCount * amount</code> exceeding the stacksize of the result item, the actual amount of crafted recipes may need to be corrected to be smaller than <code>amount</code>. For ease of use, this corrected, actual amount of crafting iterations is returned.
|}

Digital Crafter

2026-08-25T15:38:12Z

GHXX:

Digital Crafter

2026-08-25T15:35:53Z

GHXX:

JLuaVM

2026-08-25T15:21:53Z

GHXX: /* Additional standard library functions */

The JLuaVM, is the runtime that executes the Lua code that is running on computers in [[Advanced Computers]]. The source can be found [https://github.com/MidnightMages/JLuaVM on GitHub]. The most important feature for Advanced Computers is the ability to save and restore the Lua execution state, regardless of what Lua code may be loaded. We are not aware of any Java based Lua runtime being capable of this, hence why this project was born in the first place.

While we try to keep things very similar, there are a few tiny differences, listed below. In the remainder of this article, LuaC refers to PUC-Rio's implementation of Lua. If you spot a difference between JLuaVM and LuaC which is not listed here, please open a ticket at https://github.com/MidnightMages/JLuaVM/issues with a snippet that functions differently between JLuaVM and LuaC.

If you would like to contribute please see https://github.com/MidnightMages/JLuaVM/tree/master#contributing.

== LuaC deviations ==
In these cases JLuaVM (referred to as 'we') behaves differently than LuaC, '''but we still fulfill the Lua specification'''.

{| class="wikitable"
|+
!Area
!Description
|-
|Indexing of strings
|In LuaC indexing a string, where the index value <code>someIndex</code> can be an arbitrary value, always evaluates to <code>nil</code>. We argue that this is inconsistent and is almost never wanted behaviour. Therefore we instead throw an error just like indexing any other non-indexable type.<syntaxhighlight lang="lua" line="1">
("someString")[someIndex]
</syntaxhighlight>
|-
|Length of strings
|We intentionally return the number of characters instead of the length in bytes.
|-
|assert
|Produces a slightly different error message. Further, the message argument (second argument) is <code>tostring()</code>'ed before printing. This means that when the second argument happens to be a boolean, we properly print the value instead of simply stating that it was a boolean.
The following snippet will raise an error (as the first argument is falsy) and the message is simply the constant <code>true</code> represented as a string.<syntaxhighlight lang="lua" line="1">
assert(false, true)
</syntaxhighlight>
|-
|ipairs
|In our case, ipairs only allows iterating over tables. LuaC would return nil when operating on a string and error when passing a type that is neither a string nor a table. For robustness we throw on all non-table arguments as it seems very unlikely that a string is passed intentionally.
|-
|pairs
|The order in which the items are returned may differ from LuaC.
|-
|table.insert
|In LuaC this function seems to behave differently depending on whether the table is a sequence or an actual dictionary. In our case table.insert behaves identical in both cases.
|-
|table.remove
|behaviour differs slightly as the table-length operator behaves differently.
|-
|Printing numbers
|We print numbers with a few more digits of precision.
|-
|Stacktraces are formatted differently
|Due to the lack of a <code>loadfile</code> function, the chunkname is directly fed into stacktraces, allowing for specifying filenames, etc. without being surrounded by quotes. Also some things are named slightly different within the stacktrace. This indirectly also affects the <code>error(msg [, level])</code> function when <code>msg</code> is directly a <code>string</code> and <code>level == nil or level > 0</code>, and thus, part of the stacktrace is appended.
|}

== Lua language spec deviations ==
In this one case we '''do not''' follow the spec.
{| class="wikitable"
!Area
!Description
|-
|math.randomseed(seed)
|This function does not accept two seeds, but instead only one. Similarly it also only returns one number. Extra arguments are ignored.
|}

== Lua language spec extensions ==
We have also slightly extended the existing specification.

=== OOP callable constants ===
The following expression is not syntactically allowed in LuaC: <code>"someString":sub(1,3)</code>. In LuaC this would need to instead be written as <code>("someString"):sub(1,3)</code>. But as there is no grammatical conflict, we simply treat them the same.

=== Type Extension Methods ===
LuaC supports setting type-metatables using <code>debug.setmetatable</code>, e.g. for the string type. This, to our knowledge, however only works on a global level, so you cannot easily configure this on a per-environment (as in <code>_ENV</code>) setting.

We have therefore added support for what we call "Type Extension Methods", as they behave similarly to extension methods in C#. If an index operation fails and would normally result in an error, we try to perform a lookup in a subtable of <code>_EXT</code>.

For example, the following code <code>"test":sub(1,3)</code> is processed as follows:

* "test" is a string, hence is not indexable, nor can it contain a metatable, so we immediately check for an extension function (or throw an index error otherwise)
* Thus we check for <code>_ENV["_EXT"]["string"]["sub"]</code>, which by default does exist, as <code>_ENV._EXT.string</code> is set to a table that contains most of the string-library functions.

In more general terms we access <code>_ENV["_EXT][NAME OF TYPE][NAME OF FUNCTION]</code> (where <code>_ENV</code> is often equivalent to <code>_G</code>). If no match is found, we simply raise the usual error.

== Additional standard library functions ==
This is a list of all additional callable, non-standard functions provided by JLuaVM.
{| class="wikitable"
!Function
!Returns
!Description
|-
|<code>vm.listUdKeys(obj:userdata)</code>
|<code>table</code>
|Returns a table whose keys are all values that are readable or writable in the given userdata object <code>obj</code>. The value of each key is either <code>r</code>, <code>w</code> or <code>rw</code>, depending on whether the key is readable writable or readwrite.
|-
| rowspan="3" |<code>coroutine.resumeWithTimeout(co:thread, timeout:number, ...)</code>
| style="padding:0;" |<code>true, ...</code>
|The coroutine has yielded on its own. Any arguments supplied to <code>coroutine.yield(...)</code>, are returned after <code>true</code>.
|-
|<code>false, any:errorMessage</code>
|The coroutine has errored.
|-
|<code>"preempted"</code>
|The coroutine has exceeded the execution <code>timeout</code> (given in seconds) and has been forcefully paused. In this event <code>coroutine.status(co)</code> will return <code>"preempted_resumable"</code>. Any child coroutines that were currently running at the time of yielding will enter the state <code>"preempted_blocked"</code>. Attempting to <code>resume()</code> such <code>preempted_blocked</code> coroutines will throw an error.
|-
|<code>coroutine.status(co:thread)</code>
|<code>string</code>
|For completeness, this function may return all of the LuaC states <code>suspended</code>, <code>running</code>, <code>normal</code> and <code>dead</code> as well as <code>preempted_resumable</code> and <code>preempted_blocked</code>.
Resumable states are <code>suspended</code> and <code>preempted_resumable</code>.
|}
Further functionality that is NOT available in [[Advanced Computers]].
{| class="wikitable"
!Function
!Returns
!Description
|-
|<code>vm.pause()</code>
|<code>void</code>
|Immediately pauses the current LuaVM.
|}

{{Navbox content}}

JLuaVM

2026-08-25T15:20:25Z

GHXX: /* Additional standard library functions */

The JLuaVM, is the runtime that executes the Lua code that is running on computers in [[Advanced Computers]]. The source can be found [https://github.com/MidnightMages/JLuaVM on GitHub]. The most important feature for Advanced Computers is the ability to save and restore the Lua execution state, regardless of what Lua code may be loaded. We are not aware of any Java based Lua runtime being capable of this, hence why this project was born in the first place.

While we try to keep things very similar, there are a few tiny differences, listed below. In the remainder of this article, LuaC refers to PUC-Rio's implementation of Lua. If you spot a difference between JLuaVM and LuaC which is not listed here, please open a ticket at https://github.com/MidnightMages/JLuaVM/issues with a snippet that functions differently between JLuaVM and LuaC.

If you would like to contribute please see https://github.com/MidnightMages/JLuaVM/tree/master#contributing.

== LuaC deviations ==
In these cases JLuaVM (referred to as 'we') behaves differently than LuaC, '''but we still fulfill the Lua specification'''.

{| class="wikitable"
|+
!Area
!Description
|-
|Indexing of strings
|In LuaC indexing a string, where the index value <code>someIndex</code> can be an arbitrary value, always evaluates to <code>nil</code>. We argue that this is inconsistent and is almost never wanted behaviour. Therefore we instead throw an error just like indexing any other non-indexable type.<syntaxhighlight lang="lua" line="1">
("someString")[someIndex]
</syntaxhighlight>
|-
|Length of strings
|We intentionally return the number of characters instead of the length in bytes.
|-
|assert
|Produces a slightly different error message. Further, the message argument (second argument) is <code>tostring()</code>'ed before printing. This means that when the second argument happens to be a boolean, we properly print the value instead of simply stating that it was a boolean.
The following snippet will raise an error (as the first argument is falsy) and the message is simply the constant <code>true</code> represented as a string.<syntaxhighlight lang="lua" line="1">
assert(false, true)
</syntaxhighlight>
|-
|ipairs
|In our case, ipairs only allows iterating over tables. LuaC would return nil when operating on a string and error when passing a type that is neither a string nor a table. For robustness we throw on all non-table arguments as it seems very unlikely that a string is passed intentionally.
|-
|pairs
|The order in which the items are returned may differ from LuaC.
|-
|table.insert
|In LuaC this function seems to behave differently depending on whether the table is a sequence or an actual dictionary. In our case table.insert behaves identical in both cases.
|-
|table.remove
|behaviour differs slightly as the table-length operator behaves differently.
|-
|Printing numbers
|We print numbers with a few more digits of precision.
|-
|Stacktraces are formatted differently
|Due to the lack of a <code>loadfile</code> function, the chunkname is directly fed into stacktraces, allowing for specifying filenames, etc. without being surrounded by quotes. Also some things are named slightly different within the stacktrace. This indirectly also affects the <code>error(msg [, level])</code> function when <code>msg</code> is directly a <code>string</code> and <code>level == nil or level > 0</code>, and thus, part of the stacktrace is appended.
|}

== Lua language spec deviations ==
In this one case we '''do not''' follow the spec.
{| class="wikitable"
!Area
!Description
|-
|math.randomseed(seed)
|This function does not accept two seeds, but instead only one. Similarly it also only returns one number. Extra arguments are ignored.
|}

== Lua language spec extensions ==
We have also slightly extended the existing specification.

=== OOP callable constants ===
The following expression is not syntactically allowed in LuaC: <code>"someString":sub(1,3)</code>. In LuaC this would need to instead be written as <code>("someString"):sub(1,3)</code>. But as there is no grammatical conflict, we simply treat them the same.

=== Type Extension Methods ===
LuaC supports setting type-metatables using <code>debug.setmetatable</code>, e.g. for the string type. This, to our knowledge, however only works on a global level, so you cannot easily configure this on a per-environment (as in <code>_ENV</code>) setting.

We have therefore added support for what we call "Type Extension Methods", as they behave similarly to extension methods in C#. If an index operation fails and would normally result in an error, we try to perform a lookup in a subtable of <code>_EXT</code>.

For example, the following code <code>"test":sub(1,3)</code> is processed as follows:

* "test" is a string, hence is not indexable, nor can it contain a metatable, so we immediately check for an extension function (or throw an index error otherwise)
* Thus we check for <code>_ENV["_EXT"]["string"]["sub"]</code>, which by default does exist, as <code>_ENV._EXT.string</code> is set to a table that contains most of the string-library functions.

In more general terms we access <code>_ENV["_EXT][NAME OF TYPE][NAME OF FUNCTION]</code> (where <code>_ENV</code> is often equivalent to <code>_G</code>). If no match is found, we simply raise the usual error.

== Additional standard library functions ==
{| class="wikitable"
!Function
!Returns
!Description
|-
|<code>vm.listUdKeys(obj:userdata)</code>
|<code>table</code>
|Returns a table whose keys are all values that are readable or writable in the given userdata object <code>obj</code>. The value of each key is either <code>r</code>, <code>w</code> or <code>rw</code>, depending on whether the key is readable writable or readwrite.
|-
| rowspan="3" |<code>coroutine.resumeWithTimeout(co:thread, timeout:number, ...)</code>
| style="padding:0;" |<code>true, ...</code>
|The coroutine has yielded on its own. Any arguments supplied to <code>coroutine.yield(...)</code>, are returned after <code>true</code>.
|-
|<code>false, any:errorMessage</code>
|The coroutine has errored.
|-
|<code>"preempted"</code>
|The coroutine has exceeded the execution <code>timeout</code> (given in seconds) and has been forcefully paused. In this event <code>coroutine.status(co)</code> will return <code>"preempted_resumable"</code>. Any child coroutines that were currently running at the time of yielding will enter the state <code>"preempted_blocked"</code>. Attempting to <code>resume()</code> such <code>preempted_blocked</code> coroutines will throw an error.
|-
|<code>coroutine.status(co:thread)</code>
|<code>string</code>
|For completeness, this function may return all of the LuaC states <code>suspended</code>, <code>running</code>, <code>normal</code> and <code>dead</code> as well as <code>preempted_resumable</code> and <code>preempted_blocked</code>.
Resumable states are <code>suspended</code> and <code>preempted_resumable</code>.
|}
Further functionality that is NOT available in [[Advanced Computers]].
{| class="wikitable"
!Function
!Returns
!Description
|-
|<code>vm.pause()</code>
|<code>void</code>
|Immediately pauses the current LuaVM.
|}

{{Navbox content}}