lua/lib/builtin.lua

105 lines
4.8 KiB
Lua

-- Copyright (c) 2018. tangzx(love.tangzx@qq.com)
--
-- Licensed under the Apache License, Version 2.0 (the "License"); you may not
-- use this file except in compliance with the License. You may obtain a copy of
-- the License at
--
-- http://www.apache.org/licenses/LICENSE-2.0
--
-- Unless required by applicable law or agreed to in writing, software
-- distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-- WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-- License for the specific language governing permissions and limitations under
-- the License.
-- Built-in Types
---
--- The type *nil* has one single value, **nil**, whose main property is to be
--- different from any other value; it usually represents the absence of a
--- useful value.
---@class nil
---
--- The type *boolean* has two values, **false** and **true**. Both **nil** and
--- **false** make a condition false; any other value makes it true.
---@class boolean
---
--- The type *number* uses two internal representations, or two subtypes, one
--- called *integer* and the other called *float*. Lua has explicit rules about
--- when each representation is used, but it also converts between them
--- automatically as needed. Therefore, the programmer may choose to mostly
--- ignore the difference between integers and floats or to assume complete
--- control over the representation of each number. Standard Lua uses 64-bit
--- integers and double-precision (64-bit) floats, but you can also compile
--- Lua so that it uses 32-bit integers and/or single-precision (32-bit)
--- floats. The option with 32 bits for both integers and floats is
--- particularly attractive for small machines and embedded systems. (See
--- macro LUA_32BITS in file luaconf.h.)
---@class number
---
--- Lua can call (and manipulate) functions written in Lua and functions
--- written in C. Both are represented by the type *function*.
---@class function
---
--- The type *userdata* is provided to allow arbitrary C data to be stored in
--- Lua variables. A userdata value represents a block of raw memory. There
--- are two kinds of userdata: *full userdata*, which is an object with a block
--- of memory managed by Lua, and *light userdata*, which is simply a C pointer
--- value. Userdata has no predefined operations in Lua, except assignment
--- and identity test. By using *metatables*, the programmer can define
--- operations for full userdata values. Userdata values cannot be
--- created or modified in Lua, only through the C API. This guarantees the
--- integrity of data owned by the host program.
---@class userdata
---
--- The type *thread* represents independent threads of execution and it is
--- used to implement coroutines. Lua threads are not related to
--- operating-system threads. Lua supports coroutines on all systems, even those
--- that do not support threads natively.
---@class thread
---
--- The type *table* implements associative arrays, that is, arrays that can
--- have as indices not only numbers, but any Lua value except **nil** and NaN.
--- (*Not a Number* is a special floating-point value used by the IEEE 754
--- standard to represent undefined or unrepresentable numerical results, such
--- as `0/0`.) Tables can be heterogeneous; that is, they can contain values of
--- all types (except **nil**). Any key with value **nil** is not considered
--- part oft he table. Conversely, any key that is not part of a table has an
--- a ssociated value **nil**.
---
--- Tables are the sole data-structuring mechanism in Lua; they can be used to
--- represent ordinary arrays, lists, symbol tables, sets, records, graphs,
--- trees, etc. To represent records, Lua uses the field name as an index. The
--- language supports this representation by providing `a.name` as syntactic
--- sugar for `a["name"]`. There are several convenient ways to create tables
--- in Lua.
---
--- Like indices, the values of table fields can be of any type. In particular,
--- because functions are first-class values, table fields can contain functions.
--- Thus tables can also carry *methods*.
---
--- The indexing of tables follows the definition of raw equality in the
--- language. The expressions `a[i]` and `a[j]` denote the same table element
--- if and only if `i` and `j` are raw equal (that is, equal without
--- metamethods). In particular, floats with integral values are equal to
--- their respective integers. To avoid ambiguities, any float with integral
--- value used as a key is converted to its respective integer. For instance,
--- if you write `a[2.0] = true`, the actual key inserted into the table will
--- be the integer `2`. (On the other hand, 2 and "`2`" are different Lua
--- values and therefore denote different table entries.)
---@class table
---
--- Any of the above Built-in Types.
---@class any
---
---@class void
---@class self