String¶

A String is an immutable sequence of characters in kOS.

Creating strings¶

Unlike other structures, strings are created with a special syntax:

// Create a new string
SET s TO "Hello, Strings!".

Strings are immutable. This means, once a string has been created, it can not be directly modified. However, new strings can be created out of existing strings. For example:

// Create a new string with "Hello" replaced with "Goodbye"
SET s TO "Hello, Strings!".
SET t TO s:REPLACE("Hello", "Goodbye").

CASE SENSITIVIY¶

NOTE: All string comparisons, substring matches, and searches, are currently case in sensive, meaning that for example the letter “A” and the letter “a” are indistinguishable. There are future plans to add mechanisms that will let you choose case-sensitivity when you prefer.

Structure¶

structure String¶

Members¶
Suffix	Type	Description
`CONTAINS(string)`	boolean	True if the given string is contained within this string
`ENDSWITH(string)`	boolean	True if this string ends with the given string
`FIND(string)`	integer	Returns the index of the first occurrence of the given string in this string (starting from 0)
`FINDAT(string, startAt)`	integer	Returns the index of the first occurrence of the given string in this string (starting from startAt)
`FINDLAST(string)`	integer	Returns the index of the last occurrence of the given string in this string (starting from 0)
`FINDLASTAT(string, startAt)`	integer	Returns the index of the last occurrence of the given string in this string (starting from startAt)
`INDEXOF(string)`	integer	Alias for FIND(string)
`INSERT(index, string)`	`String`	Returns a new string with the given string inserted at the given index into this string
`LASTINDEXOF(string)`	integer	Alias for FINDLAST(string)
`LENGTH`	integer	Number of characters in the string
`PADLEFT(width)`	`String`	Returns a new right-aligned version of this string padded to the given width by spaces
`PADRIGHT(width)`	`String`	Returns a new left-aligned version of this string padded to the given width by spaces
`REMOVE(index,count)`	`String`	Returns a new string out of this string with the given count of characters removed starting at the given index
`REPLACE(oldString, newString)`	`String`	Returns a new string out of this string with any occurrences of oldString replaced with newString
`SPLIT(separator)`	`String`	Breaks this string up into a list of smaller strings on each occurrence of the given separator
`STARTSWITH(string)`	boolean	True if this string starts with the given string
`SUBSTRING(start, count)`	`String`	Returns a new string with the given count of characters from this string starting from the given start position
`TOLOWER`	`String`	Returns a new string with all characters in this string replaced with their lower case versions
`TOUPPER`	`String`	Returns a new string with all characters in this string replaced with their upper case versions
`TRIM`	`String`	returns a new string with no leading or trailing whitespace
`TRIMEND`	`String`	returns a new string with no trailing whitespace
`TRIMSTART`	`String`	returns a new string with no leading whitespace

String:CONTAINS(string)¶

Parameters:	string – `String` to look for
Return type:	boolean

True if the given string is contained within this string.

String:ENDSWITH(string)¶

Parameters:	string – `String` to look for
Return type:	boolean

True if this string ends with the given string.

String:FIND(string)¶

Parameters:	string – `String` to look for
Return type:	`String`

Returns the index of the first occurrence of the given string in this string (starting from 0).

String:FINDAT(string, startAt)¶

Parameters:	string – `String` to look for startAt – integer index to start searching at
Return type:	`String`

Returns the index of the first occurrence of the given string in this string (starting from startAt).

String:FINDLAST(string)¶

Parameters:	string – `String` to look for
Return type:	`String`

Returns the index of the last occurrence of the given string in this string (starting from 0)

String:FINDLASTAT(string, startAt)¶

Parameters:	string – `String` to look for startAt – integer index to start searching at
Return type:	`String`

Returns the index of the last occurrence of the given string in this string (starting from startAt)

String:INDEXOF(string)¶: Alias for FIND(string)

String:INSERT(index, string)¶

Parameters:	index – integer index to add the string at string – `String` to insert
Return type:	`String`

Returns a new string with the given string inserted at the given index into this string

String:LASTINDEXOF(string)¶: Alias for FINDLAST(string)

String:LENGTH¶

Type:	integer
Access:	Get only

Number of characters in the string

String:PADLEFT(width)¶

Parameters:	width – integer number of characters the resulting string will contain
Return type:	`String`

Returns a new right-aligned version of this string padded to the given width by spaces.

String:PADRIGHT(width)¶

Parameters:	width – integer number of characters the resulting string will contain
Return type:	`String`

Returns a new left-aligned version of this string padded to the given width by spaces.

String:REMOVE(index,count)¶

Parameters:	index – integer position of the string from which characters will be removed from the resulting string count – integer number of characters that will be removing from the resulting string
Return type:	`String`

Returns a new string out of this string with the given count of characters removed starting at the given index.

String:REPLACE(oldString,newString)¶

Parameters:	oldString – `String` to search for newString – `String` that all occurances of oldString will be replaced with
Return type:	`String`

Returns a new string out of this string with any occurrences of oldString replaced with newString.

String:SPLIT(separator)¶

Parameters:	separator – `String` delimiter on which this string will be split
Returns:	`List`

Breaks this string up into a list of smaller strings on each occurrence of the given separator. This will return a list of strings, none of which will contain the separator character(s).

String:STARTSWITH(string)¶

Parameters:	string – `String` to look for
Return type:	boolean

True if this string starts with the given string .

String:SUBSTRING(start,count)¶

Parameters:	start – (integer) starting index (from zero) count – (integer) resulting length of returned `String`
Returns:	`String`

Returns a new string with the given count of characters from this string starting from the given start position.

String:TOLOWER¶

Type:	`String`
Access:	Get only

Returns a new string with all characters in this string replaced with their lower case versions

String:TOUPPER¶

Type:	`String`
Access:	Get only

Returns a new string with all characters in this string replaced with their upper case versions

String:TRIM¶

Type:	`String`
Access:	Get only

returns a new string with no leading or trailing whitespace

String:TRIMEND¶

Type:	`String`
Access:	Get only

returns a new string with no trailing whitespace

String:TRIMSTART¶

Type:	`String`
Access:	Get only

returns a new string with no leading whitespace

Access to Individual Characters¶

All string indexes start counting at zero. (The characters are numbered from 0 to N-1 rather than from 1 to N.)

string[expression]: operator: access the character at position ‘expression’. Any arbitrary complex expression may be used with this syntax, not just a number or variable name.
FOR VAR IN STRING { ... }.: A type of loop in which var iterates over all the characters of the string from 0 to LENGTH-1.

Examples:

                                                                // CORRECT OUTPUTS
SET s TO "Hello, Strings!".                                     // ---------------
PRINT "Original String:               " + s.                    // Hello, Strings!
PRINT "string[7]:                     " + s[7].                 // S
PRINT "LENGTH:                        " + s:LENGTH.             // 15
PRINT "SUBSTRING(7, 6):               " + s:SUBSTRING(7, 6).    // String
PRINT "CONTAINS(''ring''):            " + s:CONTAINS("ring").   // True
PRINT "CONTAINS(''bling''):           " + s:CONTAINS("bling").  // False
PRINT "ENDSWITH(''ings!''):           " + s:ENDSWITH("ings!").  // True
PRINT "ENDSWITH(''outs!''):           " + s:ENDSWITH("outs").   // False
PRINT "FIND(''l''):                   " + s:FIND("l").          // 2
PRINT "FINDLAST(''l''):               " + s:FINDLAST("l").      // 3
PRINT "FINDAT(''l'', 0):              " + s:FINDAT("l", 0).     // 2
PRINT "FINDAT(''l'', 3):              " + s:FINDAT("l", 3).     // 3
PRINT "FINDLASTAT(''l'', 9):          " + s:FINDLASTAT("l", 9). // 3
PRINT "FINDLASTAT(''l'', 2):          " + s:FINDLASTAT("l", 2). // 2
PRINT "INSERT(7, ''Big ''):           " + s:INSERT(7, "Big ").  // Hello, Big Strings!

PRINT " ".
PRINT "                               |------ 18 ------|".
PRINT "PADLEFT(18):                   " + s:PADLEFT(18).        //    Hello, Strings!
PRINT "PADRIGHT(18):                  " + s:PADRIGHT(18).       // Hello, Strings!
PRINT " ".

PRINT "REMOVE(1, 3):                  " + s:REMOVE(1, 3).               // Ho, Strings!
PRINT "REPLACE(''Hell'', ''Heaven''): " + s:REPLACE("Hell", "Heaven").  // Heaveno, Strings!
PRINT "STARTSWITH(''Hell''):          " + s:STARTSWITH("Hell").         // True
PRINT "STARTSWITH(''Heaven''):        " + s:STARTSWITH("Heaven").       // False
PRINT "TOUPPER:                       " + s:TOUPPER().                  // HELLO, STRINGS!
PRINT "TOLOWER:                       " + s:TOLOWER().                  // hello, strings!

PRINT " ".
PRINT "''  Hello!  '':TRIM():         " + "  Hello!  ":TRIM().          // Hello!
PRINT "''  Hello!  '':TRIMSTART():    " + "  Hello!  ":TRIMSTART().     // Hello!
PRINT "''  Hello!  '':TRIMEND():      " + "  Hello!  ":TRIMEND().       //   Hello!

PRINT " ".
PRINT "Chained: " + "Hello!":SUBSTRING(0, 4):TOUPPER():REPLACE("ELL", "ELEPHANT").  // HELEPHANT