table

Table manipulation functions of Lua 5.1 / LuaJIT 2.1. Most of them work on the array part of a table, indices 1 to #t.

Functions

table.concat(t: table, sep?: string = "", i?: number = 1, j?: number = #t): string

table.concat(t: table, sep?: string = "", i?: number = 1, j?: number = #t): string

• Returns t[i] .. sep .. t[i+1] ... t[j].
• Elements must be strings or numbers; any other type raises an error.
• Returns an empty string if i > j.

print(table.concat({ "a", "b", "c" }, ", "))

table.foreach(t: table, f: function): any

table.foreach(t: table, f: function): any

• Calls f(key, value) for every pair of t, in unspecified order.
• Stops and returns the first non-nil value returned by f. Returns nothing if f never returns a non-nil value.
• Deprecated; prefer pairs.

table.foreachi(t: table, f: function): any

table.foreachi(t: table, f: function): any

• Calls f(index, value) for indices 1 to #t, in order.
• Stops and returns the first non-nil value returned by f.
• Deprecated; prefer ipairs.

table.getn(t: table): number

table.getn(t: table): number

• Returns the length of t. Same as #t. Deprecated.

table.insert(t: table, pos?: number, value: any)

table.insert(t: table, pos?: number, value: any)

• table.insert(t, value) appends value at position #t + 1.
• table.insert(t, pos, value) inserts value at pos and shifts the elements pos to #t up by one. pos must be in 1 to #t + 1.

local t = { 1, 2, 3 }
table.insert(t, 4)
table.insert(t, 1, 0)

table.maxn(t: table): number

table.maxn(t: table): number

• Returns the largest positive numeric key of t, or 0 if there is none. It traverses the whole table, so it also works on tables with holes.

table.remove(t: table, pos?: number = #t): any

table.remove(t: table, pos?: number = #t): any

• Removes the element at pos and shifts the following elements down by one. Returns the removed value.
• Returns nothing if the table is empty or pos is out of range.

table.sort(t: table, comp?: function)

table.sort(t: table, comp?: function)

• Sorts the elements t[1] to t[#t] in place.
• comp(a, b) must return true when a must come before b. By default the < operator is used.
• The sort is not stable. An inconsistent comp (for example using <=) can raise an "invalid order function" error.

local t = { 3, 1, 2 }
table.sort(t, function(a, b) return a > b end)