str.md

str

String utilities.

use "str"

upper / lower

str.upper("hello")   # HELLO
str.lower("HELLO")   # hello

trim

Removes leading and trailing whitespace.

str.trim("  hello  ")   # hello

contains

Returns true if the string contains the substring.

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

starts_with / ends_with

str.starts_with("hello", "he")   # true
str.ends_with("hello", "lo")     # true

replace

Replaces all occurrences of a substring.

str.replace("hello", "l", "r")   # herro

split

Splits a string by a separator. Returns an array.

parts = str.split("a,b,c", ",")
puts parts   # ["a", "b", "c"]

index

Returns the index of the first occurrence of a substring, or -1 if not found.

str.index("hello", "ll")    # 2
str.index("hello", "xyz")   # -1

join

Joins an array into a string with the given separator.

parts = ["a=1", "b=2", "c=3"]
str.join(parts, "&")   # "a=1&b=2&c=3"
str.join([1, 2, 3], "-")   # "1-2-3"

rune_count

Returns the number of Unicode characters (runes) in a string. Unlike len, which returns byte count, rune_count counts visible characters.

str.rune_count("hello")   # 5
str.rune_count("café")    # 4 (len returns 5)
str.rune_count("日本語")   # 3

count

Counts non-overlapping occurrences of a substring.

str.count("hello world", "l")   # 3
str.count("aaa", "aa")          # 1

repeat

Repeats a string n times.

str.repeat("ab", 3)   # "ababab"
str.repeat("x", 0)    # ""

reverse

Reverses a string by Unicode characters.

str.reverse("hello")   # "olleh"
str.reverse("café")    # "éfac"

chars

Splits a string into an array of individual characters.

str.chars("hi")     # ["h", "i"]
str.chars("café")   # ["c", "a", "f", "é"]

fields

Splits a string by whitespace into an array of words.

str.fields("  a  b  c  ")   # ["a", "b", "c"]

trim_prefix / trim_suffix

Removes a prefix or suffix from a string if present.

str.trim_prefix("hello", "he")   # "llo"
str.trim_suffix("hello", "lo")   # "hel"

pad_left

Left-pads a string to a given width. Optional third argument is the pad character (default: space).

str.pad_left("hi", 5)        # "   hi"
str.pad_left("hi", 5, "0")   # "000hi"

pad_right

Right-pads a string to a given width. Optional third argument is the pad character (default: space).

str.pad_right("hi", 5)        # "hi   "
str.pad_right("hi", 5, ".")   # "hi..."

center

Centers a string within a given width. Optional third argument is the pad character (default: space).

str.center("hi", 6)        # "  hi  "
str.center("hi", 6, "-")   # "--hi--"

each_line

Splits a string into an array of lines.

lines = str.each_line("a\nb\nc")   # ["a", "b", "c"]

last_index

Returns the index of the last occurrence of a substring, or -1 if not found.

str.last_index("hello", "l")     # 3
str.last_index("hello", "xyz")   # -1

slice

Extracts a substring by rune start and end indices. Supports negative indices (counted from end).

str.slice("hello", 1, 3)     # "el"
str.slice("hello", -3, -1)   # "ll"
str.slice("café", 3, 4)      # "é"

empty

Returns true if the string is empty.

str.empty("")    # true
str.empty("x")   # false