Section Tables

tables utility functions.

Summary

Return type	Function and summary
	ArrayClear(table t) Optimization of clearing a table.
boolean	ArrayContains(table tab, term) Does tab contains term?
table, int, int, int	CompareTables(table lines1, table lines2) Compare two tables, returns a diff-like format.
boolean	IN(term, ...) Check if `term` is in the list of following arguments.
boolean	assertInArray(value, table t, string text, boolean visual) Assert a value is found in a table.
boolean	isTable(obj) Returns `true` if `obj` is a table or a MyrScript object represented as a table such as Score or Target.
	longest_common_subsequence(a, b) Longest Common Subsequence (LCS) algorithm, basis for data comparison.
string	string_join(table list, string delimiter) Concat the elements of table `list`, separated by the string `delimiter`.
table	string_split(string s, string delim, int limit) Split the string `s` by a string delimiter `delim`.
table	string_split_lines(string s) Split the string `s` by lines, handle `\r`, `\n` and `\r\n`.
	table_insert_multi(table t, ...) Insert multiple items in a table in one call.
	tdebug(...) Return the structure of a table, Collection or Map for debugging to the console.

Functions

assertInArray(value, table t, string text, boolean visual)

Assert a value is found in a table.

Parameter	Type	Default	Description
value			number or string. `nil` always fails the assertion.
t	table		List of values in which `value` is searched for.
text	string		Text to print on console and throw if `expr ~= expected`
visual	boolean	false	Visual alert. Does not stop the script with a console error message, returns `true` if assertion is correct, `nil` if it fails. Your script must handle the returned value to stop gracefully.

Return: boolean: true if assertion is correct, nil (for false) if it failed. If visual ~= true, no need to check the returned value, script will die with a console error.
Error: If value not found in t

IN(term, ...)

Check if term is in the list of following arguments.

Parameter	Type	Default	Description
term			string, number or objects that support `==` comparison
...			List of arguments, of undefined length. If one (or more) arguments are table, Collection or Map then `term` is searched in their items. Note that Collection and Map values must have the same type than `type(term)`.

Return: boolean: true if the list contains term, nil (for false) if the list doesn't contains term
See: ArrayContains

isTable(obj)

Returns true if obj is a table or a MyrScript object represented as a table such as Score or Target.

Parameter	Type	Default	Description
obj			obj

Return: boolean: boolean

ArrayClear(table t)

Optimization of clearing a table.

tremove is time consuming because it shift all items after the removed one.
tremove from last to first would be a bit faster.
but setting items to nil is even faster.

Parameter	Type	Default	Description
t	table		The table to clear.

ArrayContains(table tab, term)

Does tab contains term?

Parameter	Type	Default	Description
tab	table		A table of numbers or strings
term			A number or a string to find in tab

Return: boolean: true, or nil (for false)
Error: if tab's items are not comparable with term

tdebug(...)

Return the structure of a table, Collection or Map for debugging to the console.

Parameter	Type	Default	Description
...			Structure(s) to debug

table_insert_multi(table t, ...)

Insert multiple items in a table in one call.

Parameter	Type	Default	Description
t	table		t
...			Undefined number of arguments

longest_common_subsequence(a, b)

Longest Common Subsequence (LCS) algorithm, basis for data comparison.

This compares 2 strings or tables (of numbers or strings) and returns a string or a table containing common chars or items.
For the two strings "ABC" and "ACE", the LCS is "AC".

Parameter	Type	Default	Description
a			First string or table (of comparable elements)
b			Second string or table (of comparable elements)

Return: A string if a and b are strings, else a table.
Error: if type(a) ~= type(b)
See: CompareTextFiles; CompareTables; CompareStrings; https://en.wikipedia.org/wiki/Longest_common_subsequence; https://www.geeksforgeeks.org/dsa/longest-common-subsequence-dp-4/

CompareTables(table lines1, table lines2)

Compare two tables, returns a diff-like format.

The diff format is used for data comparison, or, in development environnement, to compare old and new lines of source code.

tables in arguments must contain comparable (==) and tostring()able items: so it's restricted to numbers and strings. For complex datas, consider serialization.

Parameter	Type	Default	Description
lines1	table		First (oldest) table of strings
lines2	table		Second (newest) table of strings

Returns

table: Lines in approximate diff format:

Added lines start with a + (plus)
Removed lines start with a - (minus)
Common lines (unchanged) start with a space.

int: Number of added lines

int: Number of removed lines

int: Number of unchanged lines

See

CompareTextFiles

CompareStrings

string_split(string s, string delim, int limit)

Split the string s by a string delimiter delim.

Parameter	Type	Default	Description
s	string		The string to split
delim	string		The delimiter
limit	int	0	Maximum number of slices of string, values `<= 1` are ignored..

Return

table: An array of at least one item (s if delim is not found)

Example


local t = string_split("Hello World!", " ")
 print(t[1]) --> Hello
 print(t[2]) --> World!

string_split_lines(string s)

Split the string s by lines, handle \r, \n and \r\n.

Parameter	Type	Default	Description
s	string		The string to split

Return: table: A table of at least one element (s if line separator is not found)

string_join(table list, string delimiter)

Concat the elements of table list, separated by the string delimiter.

Parameter	Type	Default	Description
list	table		list
delimiter	string	""