ComputerCraft Wiki - User contributions [en]

User:Creator

2015-06-20T14:00:32Z

Creator:

Hi folks, this is my Wiki account.

Nice, don't you think?

Be sure to visit <span class="plainlinks">[http://www.computercraft.info/forums2/index.php?/user/33826-creator/ me]</span> on the forums!

User:Creator

2015-06-20T13:59:52Z

Creator:

Hi folks, this is my Wiki account.

Nice, don't you think?

Be sure to visit [http://www.computercraft.info/forums2/index.php?/user/33826-creator/ me] on the forums!

User:Creator

2015-06-20T13:45:55Z

Creator: Created page with "Hi folks, this is my Wiki account. Nice, don't you think? Be sure to visit [me = http://www.computercraft.info/forums2/index.php?/user/33826-creator/] on the forums!"

Hi folks, this is my Wiki account.

Nice, don't you think?

Be sure to visit [me = http://www.computercraft.info/forums2/index.php?/user/33826-creator/] on the forums!

Delete

2015-05-08T14:18:49Z

Creator:

{{Stub|Needs more info about the program itself, perhaps an image?}}
Delete is a [[CraftOS Shell|built in program for computers and turtles]] that will delete the specified source file or directory. As of version 1.6, it supports wildcards by use of [[fs.find]]. It ''cannot'' remove read-only files such as the rom folder or anything in the rom folder. Instead of delete, it is also possible to use rm (remove).

{{Example
|desc=Removes regular file /foo
|code=delete /foo
}}

{{Example
|desc=Removes all the files and directories
|code=delete *
}}

[[Category:Programs]]

Delete

2015-05-08T14:17:22Z

Creator:

{{Stub|Needs more info about the program itself, perhaps an image?}}
Delete is a [[CraftOS Shell|built in program for computers and turtles]] that will delete the specified source file or directory. As of version 1.6, it supports wildcards by use of [[fs.find]]. It ''cannot'' remove read-only files such as the rom folder or anything in the rom folder.

{{Example
|desc=Removes regular file /foo
|code=delete /foo
}}

{{Example
|desc=Removes all the files and directories
|code=delete *
}}

[[Category:Programs]]

Delete

2015-05-08T14:16:59Z

Creator:

{{Stub|Needs more info about the program itself, perhaps an image?}}
Delete is a [[CraftOS Shell|built in program for computers and turtles]] that will delete the specified source file or directory. As of version 1.6, it supports wildcards by use of [[fs.find]]. It ''cannot'' remove read-only files such as the rom folder or anything in the rom folder.

{{Examples
|desc=Removes regular file /foo
|code=delete /foo
}}
{{Example
|desc=Removes all the files and directories
|code=delete *
}}

[[Category:Programs]]

Delete

2015-05-08T14:16:09Z

Creator:

{{Stub|Needs more info about the program itself, perhaps an image?}}
Delete is a [[CraftOS Shell|built in program for computers and turtles]] that will delete the specified source file or directory. As of version 1.6, it supports wildcards by use of [[fs.find]]. It ''cannot'' remove read-only files such as the rom folder or anything in the rom folder.

{{Examples
|desc=Removes regular file /foo
|code=delete /foo
|desc=Removes all the files and directories
|code=delete *
}}

[[Category:Programs]]

Os.loadAPI

2015-05-08T14:10:36Z

Creator: Small inversion removed

{{Lowercase}}
{{Function
|name=os.loadAPI
|args={{type|string}} path
|api=OS
|returns={{type|boolean}} did the API load successfully?
|addon=ComputerCraft
|desc=Loads a user created API from a file located at <var>path</var>.
<br/>
This function runs the file, collects all global (non-localized) variables from it and puts them into a [[table_(type)|table]] into the global (<var>_G</var>) environment. The name of the file becomes the name of the table.
|examples={{Example
|desc=Loads an API saved at "''test/myAPI''" and runs the global function "''hello''" from it.
|code='''''--test/myAPI:'''''

local text = "Hello World!" ''-- this won't be seen from outside of the API because it is localized''

function hello () ''-- this will be seen from outside the API because it is '''not''' localized''
[[print]](text)
end

'''''--The program that will use "myAPI"'''''

'''os.loadAPI("test/myAPI")''' ''-- load the API''

myAPI.hello() ''-- runs the function "hello" from the API''
|output=Hello World!
}}
|notes=
* <var>path</var> '''must''' be an absolute path.
* All variables which will be needed to be accessed through ''<apiname>.<variable/function>'' '''must''' be global.
* By default APIs '''cannot''' access [[shell_(API)|shell API]] and [[multishell_(API)|multishell API]].
}}

Coal

2015-05-07T21:48:49Z

Creator: Added some info

{{Stub}}
Coal is a item added by vanilla Minecraft. It is used as a fuel for Turtles. It has a refuel value of 80.

[http://www.minecraftwiki.net/wiki/Coal| See the minecraft wiki] for more information.

It can be found underground, but, on rare occasions, spawns on the surface.

Metatable

2015-05-07T21:46:32Z

Creator:

{{NeedsWork|Not enough info, perhaps incorrect info}}

A metatable is an addition on to normal tables for adding metamethods, making classes as well as protecting functions. When a certain action is performed on a table, lua checks whether the corresponding __metatable field exists. For example, when you want to access the index bar in the table foo, but foo.bar does not exist, if the table has __index as a __metatable field, lua will call the __index field. If it's value is another table, lua will search for the index in the new table; however, if the value is a function, lua will pass the table name and the index as arguments.

== Setting and getting a metatable ==

You will use setMetatable and getMetatable to set and get metatables.

You use getMetatable(table) to get your metatable from a table. It will return the __metatable metafield
in the table.

setMetatable(table, metatable) to set your table's metatable. It will error if the __metatable metafield
is set.

However, if the table has a metatable with the metafield __metatable, it will error when you use setMetatable and return what it is set to when getMetatable is called.

== Metamethods ==

A metamethod is a type of function which changes the default way a table acts. The table below demonstrates what each
one is called, and how each one is used. <br/>

{| class="wikitable"
|-
| Name || Description || Arguments passed
|-
| __index
| Used when table[variable] is called.
| The variable.
|-
| __newindex
| Used like __index, but it is only called when the variable matches an empty space in the table.
| The variable.
|-
| __call
| A metamethod to turn a table's name into a function, or whatever you want it to do.
| Function, Tuple
|-
| __metatable
| Used for protecting metatables, called when getmetatable() is used on the table, setmetatable() just errors.
| Nothing (as far as Unit158 knows)
|-
| __mul
| Used as an operator overloader for multiplication.
| The two objects being "multiplied".
|-
| __div
| Used as an operator overloader for division.
| The two objects being "divided".
|-
| __sub
| Used as an operator overloader for substraction.
| The two objects being "subtracted".
|-
| __add
| Used as an operator overloader for addition.
| The two objects being "added".
|-
| __mod
| Used as an operator overloader for modulo.
| The two objects being "divided".
|-
| __pow
| Used as an operator overloader for exponentiation operation.
| The two objects being exponentiated.
|-
| __unm
| I am not exactly sure how this one works, it is for negatives though.
| The table being changed into a negative. 
|-
| __eq
| __eq is an operator overloader for comparison.
| The two objects being compared
|-
| __lt
| Less than.
| The two objects being compared
|-
| __le
| Less than or equal to.
| The objects being compared
|-
| __concat
| The objects being concatenated
| The two objects being concatenated
|-
| __len
| The # operator.
| The object having the operation performed on it.
|-
|}

== Examples ==
{{Example
|desc=Use __eq to check if two tables are equal
|code=table1 = {x=0, y=1, z=0}
table2 = {x=1, y=1, z=0}
metatable = {__eq = function(operand1, operand2, type)
if operand1.x == operand2.x and operand1.y == operand2.y and operand1.z then --Note: In reality you might want to first check if your these variables actually exist
return true
else
return false
end }
setmetatable(table1, metatable)
setmetatable(table2, metatable)
if table1 == table2 then
print("Equal")
else
print("Not equal")
end
}}
== External links ==
* [http://www.lua.org/manual/5.1/manual.html#2.8 Lua 5.1 Reference Manual: Metatables]

[[Category:Tutorials]]