3.2. Boost package for string manipulation library

The STRINGS_BOOST module extends string handling with splitting, joining, padding, character replacement, and edit distance computation.

All functions and symbols are in “strings_boost” module, use require to get access to it.

require daslib/strings_boost

Example:

require daslib/strings_boost

    [export]
    def main() {
        let parts = split("one,two,three", ",")
        print("split: {parts}\n")
        print("join: {join(parts, " | ")}\n")
        print("[{wide("hello", 10)}]\n")
        print("distance: {levenshtein_distance("kitten", "sitting")}\n")
    }
    // output:
    // split: [[ one; two; three]]
    // join: one | two | three
    // [hello     ]
    // distance: 3

3.2.1. Split and join

3.2.1.1. join

strings_boost::join(it: auto; separator: string) : auto()

Joins the elements of an iterable into a single string using the specified separator.

Arguments

  • it : auto

  • separator : string implicit

strings_boost::join(iterable: array<auto(TT)>; separator: string; blk: block<(var writer:StringBuilderWriter;elem:TT):void>) : string()
strings_boost::join(it: iterator<auto(TT)>; separator: string) : auto()
strings_boost::join(iterable: iterator<auto(TT)>; separator: string; blk: block<(var writer:StringBuilderWriter;elem:TT):void>) : string()
strings_boost::join(iterable: auto(TT)[]; separator: string; blk: block<(var writer:StringBuilderWriter;elem:TT):void>) : string()

3.2.1.2. split

strings_boost::split(text: string; delim: string) : array<string>()

Splits a string by the specified delimiter string and returns an array of substrings.

Arguments

  • text : string implicit

  • delim : string implicit

strings_boost::split(text: string; delim: string; blk: block<(arg:array<string>#):auto>) : auto()

3.2.1.3. split_by_chars

strings_boost::split_by_chars(text: string; delim: string) : array<string>()

Splits a string by the specified delimiter characters and returns an array of substrings.

Arguments

  • text : string implicit

  • delim : string implicit

strings_boost::split_by_chars(text: string; delim: string; blk: block<(arg:array<string>#):auto>) : auto()

3.2.2. Formatting

strings_boost::capitalize(str: string) : string()

Returns a copy of the string with the first character converted to uppercase. The rest of the string is unchanged.

Arguments

  • str : string

strings_boost::pad_left(str: string; width: int; ch: int = 32) : string()

Pads the string with the character ch on the left to reach the specified minimum width. If the string is already at least width characters, it is returned unchanged.

Arguments

  • str : string

  • width : int

  • ch : int

strings_boost::pad_right(str: string; width: int; ch: int = 32) : string()

Pads the string with the character ch on the right to reach the specified minimum width. If the string is already at least width characters, it is returned unchanged.

Arguments

  • str : string

  • width : int

  • ch : int

strings_boost::wide(text: string; width: int) : string()

Pads the string with trailing spaces to reach the specified minimum width.

Arguments

  • text : string implicit

  • width : int

3.2.3. Queries and comparisons

strings_boost::contains(str: string; sub: string) : bool()

Returns true if sub is found anywhere within str.

Arguments

  • str : string

  • sub : string

strings_boost::count(str: string; sub: string) : int()

Counts non-overlapping occurrences of sub in str. Returns 0 if sub is empty or not found.

Arguments

  • str : string

  • sub : string

3.2.3.1. eq

strings_boost::eq(b: das_string; a: string) : auto()

Compares a string with a das_string for equality, returning true if they match.

Arguments
strings_boost::eq(a: string; b: das_string) : auto()
strings_boost::is_character_at(foo: array<uint8>; idx: int; ch: int) : auto()

Returns true if the byte at the specified index in the array equals the given character code.

Arguments

  • foo : array<uint8> implicit

  • idx : int

  • ch : int

strings_boost::is_null_or_whitespace(str: string) : bool()

Returns true if the string is null, empty, or contains only whitespace characters (space, tab, CR, LF).

Arguments

  • str : string

3.2.5. Replace

strings_boost::replace_multiple(source: string; replaces: array<tuple<text:string;replacement:string>>) : string()

Applies multiple find-and-replace substitutions to a string in a single pass.

Arguments

  • source : string

  • replaces : array<tuple<text:string;replacement:string>>

3.2.6. Prefix and suffix

strings_boost::trim_prefix(str: string; prefix: string) : string()

Removes prefix from the beginning of str if present. Returns the string unchanged if it does not start with prefix.

Arguments

  • str : string

  • prefix : string

strings_boost::trim_suffix(str: string; suffix: string) : string()

Removes suffix from the end of str if present. Returns the string unchanged if it does not end with suffix.

Arguments

  • str : string

  • suffix : string

3.2.7. Levenshtein distance

strings_boost::levenshtein_distance(s: string; t: string) : int()

Computes the Levenshtein edit distance between two strings.

Arguments

  • s : string implicit

  • t : string implicit

strings_boost::levenshtein_distance_fast(s: string; t: string) : int()

Computes the Levenshtein edit distance between two strings using an optimized algorithm.

Arguments

  • s : string implicit

  • t : string implicit