std/str

String helpers. Import with import "std/str";. Available everywhere.

A string is an array of char (bytes), so these functions work byte-wise. Case conversion covers ASCII letters only. For length, indexing, and slicing use the built-in array methods (s.len(), s[i], s.slice(a, b)).

Searching

index_of

int? index_of(haystack: string, needle: string)

Returns the index of the first occurrence of needle in haystack, or none if it does not occur. An empty needle matches at index 0.

str.index_of("hello world", "world")   # 6
str.index_of("hello", "xyz")           # none

contains

bool contains(haystack: string, needle: string)

Returns true if needle occurs anywhere in haystack.

str.contains("hello world", "lo w")   # true

starts_with

bool starts_with(s: string, prefix: string)

Returns true if s begins with prefix.

ends_with

bool ends_with(s: string, suffix: string)

Returns true if s ends with suffix.

str.starts_with("main.kora", "main")   # true
str.ends_with("main.kora", ".kora")    # true

Transforming

to_upper

string to_upper(s: string)

Returns a copy of s with ASCII letters a to z uppercased.

to_lower

string to_lower(s: string)

Returns a copy of s with ASCII letters A to Z lowercased.

str.to_upper("kora 1.0")   # "KORA 1.0"
str.to_lower("KoRa")       # "kora"

trim

string trim(s: string)

Returns s without leading and trailing whitespace (spaces, tabs, newlines, carriage returns).

str.trim("  hi \n")   # "hi"

repeat

string repeat(s: string, n: int)

Returns s concatenated n times. Returns "" when n is zero or negative.

str.repeat("ab", 3)   # "ababab"

reverse

string reverse(s: string)

Returns s with its bytes in reverse order.

str.reverse("kora")   # "arok"

Splitting and joining

split

[string] split(s: string, sep: char)

Splits s at every occurrence of sep. The separator is not included in the pieces. n separators always produce n + 1 pieces, so adjacent separators yield empty strings.

str.split("a,b,c", ',')   # ["a", "b", "c"]
str.split("a,,c", ',')    # ["a", "", "c"]
str.split("abc", ',')     # ["abc"]

join

string join(parts: [string], sep: string)

Concatenates parts with sep between consecutive elements.

str.join(["usr", "local", "bin"], "/")   # "usr/local/bin"

Classifying

is_space

bool is_space(c: char)

Returns true if c is a space, tab, newline, or carriage return.

str.is_space(' ')   # true
str.is_space('x')   # false