Module table

Table Manipulation This library provides generic functions for table manipulation.

It provides all its functions inside the table table.

Most functions in the table library assume that the table represents an array or a list. For these functions, when we talk about the "length" of a table we mean the result of the length operator.

Type table

table.concat(table, sep, i, j)	Given an array where all elements are strings or numbers, returns table[i]..sep..table[i+1]...sep..table[j].
table.insert(table, pos, value)	Inserts element value at position pos in table, shifting up other elements to open space, if necessary.
table.maxn(table)	Returns the largest positive numerical index of the given table, or zero if the table has no positive numerical indices.
table.remove(table, pos)	Removes from table the element at position pos, shifting down other elements to close the space, if necessary.
table.sort(table, comp)	Sorts table elements in a given order, in-place, from table[1] to table[n], where n is the length of the table.

Type table

Field(s)

table.concat(table, sep, i, j)

Given an array where all elements are strings or numbers, returns table[i]..sep..table[i+1]...sep..table[j].

The default value for sep is the empty string, the default for i is 1, and the default for j is the length of the table. If i is greater than j, returns the empty string.

Parameters

• #table table : table to handle.

• #string sep : the separator, default value is an empty string.

• #number i : start index, default value is 1.

• #number j : end index, default value is lenght of the table.

Return value

#string: the concatenated table.

table.insert(table, pos, value)

Inserts element value at position pos in table, shifting up other elements to open space, if necessary.

The default value for pos is n+1, where n is the length of the table, so that a call table.insert(t,x) inserts x at the end of table t.

Parameters

• #table table : table to modify.

• #number pos : index of insertion.

• value : value to insert.

table.maxn(table)

Returns the largest positive numerical index of the given table, or zero if the table has no positive numerical indices.

(To do its job this function does a linear traversal of the whole table.)

Parameter

• #table table : table to traverse.

Return value

#number: the largest positive numerical index of the given table, or zero if the table has no positive numerical indices.

table.remove(table, pos)

Removes from table the element at position pos, shifting down other elements to close the space, if necessary.

Returns the value of the removed element. The default value for pos is n, where n is the length of the table, so that a call table.remove(t) removes the last element of table t.

Parameters

• #table table : table to modify.

• #number pos : index of deletion. (default value is the lenght of the table)

table.sort(table, comp)

Sorts table elements in a given order, in-place, from table[1] to table[n], where n is the length of the table.

If comp is given, then it must be a function that receives two table elements, and returns true when the first is less than the second (so that not comp(a[i+1],a[i]) will be true after the sort). Lua operator < is used instead.

The sort algorithm is not stable; that is, elements considered equal by the given order may have their relative positions changed by the sort.

Parameters

• #table table : table to sort.

• comp : a function which take to table and returns true when the first is less than the second.