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Version: 2.3.3

String

%​

pattern % [...,(k,v),...] changes in the pattern occurrences of:

  • $(k) into v
  • `$(if $(k2),"a","b") into "a" if k2 is found in the list, "b" otherwise.

Type:

(string, [string * string]) -> string

Arguments:

  • (unlabeled) (of type string)
  • (unlabeled) (of type [string * string])

^​

Concatenate strings.

Type:

(string, string) -> string

Arguments:

  • (unlabeled) (of type string)
  • (unlabeled) (of type string)

bool_of_string​

Convert a string to a bool. Raises error.failure("a string to a bool") if conversion fails and default is null

Type:

(string, ?default : bool?) -> bool

Arguments:

  • (unlabeled) (of type string)
  • default (of type bool?, which defaults to null)

file.metadata.flac.cover.decode​

Decode a flac-encoded cover metadata string.

Type:

(string) -> string
.{
  color_depth : int,
  description : string,
  height : int,
  mime : string,
  number_of_colors : int?,
  picture_type : int,
  width : int}?

Arguments:

  • (unlabeled) (of type string)

file.metadata.flac.cover.encode​

Encode cover metadata for embedding with flac files.

Type:

(picture_type : int, mime : string, ?description : string, width : int,
 height : int, color_depth : int, ?number_of_colors : int?, string) -> string

Arguments:

  • picture_type (of type int)
  • mime (of type string)
  • description (of type string, which defaults to "")
  • width (of type int)
  • height (of type int)
  • color_depth (of type int)
  • number_of_colors (of type int?, which defaults to null)
  • (unlabeled) (of type string)

float_of_string​

Convert a string to a float. Raises error.failure("a string to a float") if conversion fails and default is null

Type:

(string, ?default : float?) -> float

Arguments:

  • (unlabeled) (of type string)
  • default (of type float?, which defaults to null)

hls.playlist.main​

Generate a main HLS playlist

Type:

(?extra_tags : [string], ?prefix : string, ?version : int,
 [string.{bandwidth : int, codecs : string, video_size? : int * int}]) ->
string

Arguments:

  • extra_tags (of type [string], which defaults to [])
  • prefix (of type string, which defaults to "")
  • version (of type int, which defaults to 7)
  • (unlabeled) (of type [string.{bandwidth : int, codecs : string, video_size? : int * int}])

int_of_string​

Convert a string to a int. Raises error.failure("a string to a int") if conversion fails and default is null

Type:

(string, ?default : int?) -> int

Arguments:

  • (unlabeled) (of type string)
  • default (of type int?, which defaults to null)

irc.channel​

Contents of an IRC channel.

Type:

(?server : string, ?port : int, ?channel : string, ?nick : string,
 ?limit : int) -> () -> string

Example:

# Display messages in the #liquidsoap-test room over a video
s = single("test.mp4")
s = video.add_text.native(irc.channel(channel="#liquidsoap-test"), s)

Arguments:

  • server (of type string, which defaults to "irc.libera.chat"): IRC server.
  • port (of type int, which defaults to 6667): Port for IRC server.
  • channel (of type string, which defaults to "#liquidsoap"): IRC chan to join.
  • nick (of type string, which defaults to "liquidbot"): Nickname.
  • limit (of type int, which defaults to 10): Limit to n last messages

json​

Create a generic json object

Type:

() -> json

Methods:

  • add (of type (string, 'a) -> unit): Add or replace a new key/value pair to the object.
  • remove (of type (string) -> unit): Remove a key from the object. Does not nothing if the key does not exist.
  • stringify (of type (?compact : bool, ?json5 : bool) -> string): Render object as json string.

json.stringify​

Convert a value to JSON. If the value cannot be represented as JSON (for instance a function), a error.json exception is raised.

Type:

(?compact : bool, ?json5 : bool, 'a) -> string

Arguments:

  • compact (of type bool, which defaults to false): Output compact text.
  • json5 (of type bool, which defaults to false): Use json5 extended spec.
  • (unlabeled) (of type 'a)

metadata.id3v2.render​

Return a string representation of a id3v2 metadata tag

Type:

([string * string], ?version : int) -> string

Arguments:

  • (unlabeled) (of type [string * string])
  • version (of type int, which defaults to 3): Tag version. One of: 3 or 4

metadata.parse.amplify​

Parse an amplify metadata. Parsing is the same as in the amplify operator. Metadata can be of the form: " dB" for a decibel-based value or "" for a linear-based value. Returns a decibel value.

Type:

(string) -> float

Arguments:

  • (unlabeled) (of type string)

regexp​

Create a regular expression

Type:

(?flags : [string], string) -> regexp

Arguments:

  • flags (of type [string], which defaults to []): List of flags. Valid flags: "i", "g", "m".
  • (unlabeled) (of type string)

Methods:

  • exec (of type (string) -> [int * string].{groups : [string * string]}): Extract substrings from a string. Returns a list of (index,value). If the list does not have a pair associated to some index, it means that the corresponding pattern was not found.
  • replace (of type (((string) -> string), string) -> string): Replace substrings matched by the regexp by another string returned by a function.
  • split (of type (string) -> [string]): Split a string on the given regular expression.
  • test (of type (string) -> bool): Match a string with the expressionn.

runtime.memory.prettify_bytes​

Returns a human-redable description of an amount of bytes.

Type:

(?float_printer : ((float) -> string)?, ?signed : bool?, ?bits : bool?,
 ?binary : bool?, int) -> string

Arguments:

  • float_printer (of type ((float) -> string)?, which defaults to null)
  • signed (of type bool?, which defaults to null)
  • bits (of type bool?, which defaults to null)
  • binary (of type bool?, which defaults to null)
  • (unlabeled) (of type int)

string​

Return the representation of a value.

Type:

(?fields : bool, 'a) -> string

Arguments:

  • fields (of type bool, which defaults to false): Show toplevel fields around the value.
  • (unlabeled) (of type 'a)

string.annotate.parse​

Parse a string of the form <key>=<value>,...:<uri> as given by the annotate: protocol

Type:

(string) -> [string * string] * string

Arguments:

  • (unlabeled) (of type string)

string.base64.decode​

Decode a Base64 encoded string.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.base64.encode​

Encode a string in Base64.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.binary.of_int​

Encode a positive (unsigned) integer using native memory representation.

Type:

(?pad : int, ?little_endian : bool, int) -> string

Arguments:

  • pad (of type int, which defaults to 0): Minimum length in digits (pad on the left with zeros in order to reach it)
  • little_endian (of type bool, which defaults to true): Whether the memory representation is little endian.
  • (unlabeled) (of type int): String containing the binary representation.

string.binary.to_int​

Value of a positive (unsigned) integer encoded using native memory representation.

Type:

(?little_endian : bool, string) -> int

Arguments:

  • little_endian (of type bool, which defaults to true): Whether the memory representation is little endian.
  • (unlabeled) (of type string): String containing the binary representation.

string.bytes​

Return an array of the string's bytes.

Type:

(string) -> [string]

Arguments:

  • (unlabeled) (of type string)

string.bytes.length​

Return the length of the string in bytes.

Type:

(string) -> int

Arguments:

  • (unlabeled) (of type string)

string.capitalize​

Return a string with the first character set to upper case (capitalize), or to lower case (uncapitalize).

Type:

(?capitalize : bool, ?space_sensitive : bool, string) -> string

Arguments:

  • capitalize (of type bool, which defaults to true): Capitalize if true, uncapitalize otherwise
  • space_sensitive (of type bool, which defaults to true): Capitalize each space separated sub-string.
  • (unlabeled) (of type string)

string.case​

Convert a string to lower or upper case.

Type:

(?lower : bool, string) -> string

Arguments:

  • lower (of type bool, which defaults to true): Convert to lower case if true and uppercase otherwise.
  • (unlabeled) (of type string)

string.char​

Create a string with one character.

Type:

(int) -> string

Arguments:

  • (unlabeled) (of type int): Code of the character.

string.char.ascii​

All ASCII characters code

Type:

[int]

string.char.ascii.alphabet​

All ASCII alphabet character codes

Type:

[int]

string.char.ascii.control​

All ASCII control character codes

Type:

[int]

string.char.ascii.number​

All ASCII number character codes

Type:

[int]

string.char.ascii.printable​

All ASCII printable character codes

Type:

[int]

string.char.ascii.random​

Return a random ASCII character

Type:

(?[int]) -> string

Arguments:

  • (unlabeled) (of type [int], which defaults to [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127])

string.chars​

Split string into characters. Raises error.invalid on errors.

Type:

(?encoding : string?, string) -> [string]

Arguments:

  • encoding (of type string?, which defaults to null): Encoding used to split characters. Should be one of: "utf8" or "ascii"
  • (unlabeled) (of type string)

string.compare​

Compare strings in lexicographical order.

Type:

(string, string) -> int

Arguments:

  • (unlabeled) (of type string)
  • (unlabeled) (of type string)

string.concat​

Concatenate strings.

Type:

(?separator : string, [string]) -> string

Arguments:

  • separator (of type string, which defaults to "")
  • (unlabeled) (of type [string])

string.contains​

Test whether a string contains a given prefix, substring or suffix.

Type:

(?encoding : string?, ?prefix : string, ?substring : string,
 ?suffix : string, string) -> bool

Arguments:

  • encoding (of type string?, which defaults to null): Encoding used to split characters. Should be one of: "utf8" or "ascii"
  • prefix (of type string, which defaults to ""): Prefix to look for.
  • substring (of type string, which defaults to ""): Substring to look for.
  • suffix (of type string, which defaults to ""): Suffix to look for.
  • (unlabeled) (of type string): The string to look into.

string.data_uri.decode​

Decode a string using the data uri format, i.e. "data:<mime>[;base64],<data>".

Type:

(string) -> string.{mime : string}?

Arguments:

  • (unlabeled) (of type string)

string.data_uri.encode​

Encode a string using the data uri format, i.e. "data:<mime>[;base64],<data>".

Type:

(?base64 : bool, mime : string, string) -> string

Arguments:

  • base64 (of type bool, which defaults to true): Encode data using the base64 format
  • mime (of type string): Data mime type
  • (unlabeled) (of type string)

string.digest​

Return an MD5 digest for the given string.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.escape​

Escape special characters in an string. By default, the string is assumed to be "utf8" encoded and is escaped following JSON and javascript specification.

Type:

(?special_char : ((encoding : string, string) -> bool)?,
 ?escape_char : ((encoding : string, string) -> string)?,
 ?encoding : string?, string) -> string

Arguments:

  • special_char (of type ((encoding : string, string) -> bool)?, which defaults to null): Return true if the given character (passed as a string) should be escaped. Defaults to control characters for "utf8" and control characters and any character above \x7E (non-printable characters) for "ascii".
  • escape_char (of type ((encoding : string, string) -> string)?, which defaults to null): Function used to escape a character. Defaults to \xxx octal notation for "ascii" and \uxxxx hexadecimal notation for "utf8".
  • encoding (of type string?, which defaults to null): One of: "ascii" or "utf8". If null, utf8 is tried first and ascii is used as a fallback if this fails.
  • (unlabeled) (of type string)

string.escape.all​

Escape each character in the given string using a specific escape sequence.

Type:

(?format : string, string) -> string

Arguments:

  • format (of type string, which defaults to "utf8"): Escape format. One of: "octal", "hex" or "utf8".
  • (unlabeled) (of type string)

string.escape.html​

Escape HTML entities.

Type:

(?encoding : string?, string) -> string

Arguments:

  • encoding (of type string?, which defaults to null): One of: "ascii" or "utf8". If null, utf8 is tried first and ascii is used as a fallback if this fails.
  • (unlabeled) (of type string)

string.escape.special_char​

Default function to detect characters to escape. See string.escape for more details.

Type:

(?encoding : string, string) -> bool

Arguments:

  • encoding (of type string, which defaults to "utf8"): One of: "ascii" or "utf8".
  • (unlabeled) (of type string)

string.extract​

Extract substrings from a string. Perl compatible regular expressions are recognized. Hence, special characters should be escaped. Returns a list of (index,value). If the list does not have a pair associated to some index, it means that the corresponding pattern was not found. Alter natively, one can use the r/_/.exec(_) syntax for regular expressions.

Type:

(pattern : string, string) -> [int * string]

Arguments:

  • pattern (of type string)
  • (unlabeled) (of type string)

Methods:

  • groups (of type [string * string]): Named captures

string.float​

String representation of a float.

Type:

(?decimal_places : int?, float) -> string

Arguments:

  • decimal_places (of type int?, which defaults to null): Number of decimal places.
  • (unlabeled) (of type float)

string.getter.concat​

Combine a list of string getters [g1, ...] and return a single getter g such that: string.getter.flush(separator=s, g) = string.concat(separator=s, list.filter(fun (s) -> s != "", [string.getter.flush(g1), ...]))

Type:

([{string}]) -> {string}

Arguments:

  • (unlabeled) (of type [{string}])

string.getter.flush​

Flush all values from a string getter and return the concatenated result. If the getter is constant, return the constant string. Otherwise, call the getter repeatedly until it returns an empty string and return the concatenated result

Type:

(?separator : string, {string}) -> string

Arguments:

  • separator (of type string, which defaults to "")
  • (unlabeled) (of type {string})

string.getter.single​

Create a string getter which will return once the given string and then the empty string.

Type:

(string) -> () -> string

Arguments:

  • (unlabeled) (of type string)

string.hex_of_int​

Hexadecimal representation of an integer.

Type:

(?pad : int, int) -> string

Arguments:

  • pad (of type int, which defaults to 0): Minimum length in digits (pad on the left with zeros in order to reach it).
  • (unlabeled) (of type int)

string.id​

Generate an identifier with given operator name.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string): Operator name.

string.id.default​

Generate an identifier if no identifier was provided.

Type:

(default : string, string?) -> string

Arguments:

  • default (of type string): Name from which identifier is generated if not present.
  • (unlabeled) (of type string?): Proposed identifier.

string.index​

Index where a substring occurs in a string. The function returns -1 if the substring is not present

Type:

(substring : string, string) -> int

Arguments:

  • substring (of type string): Substring to look for.
  • (unlabeled) (of type string): String in which to look.

string.is_int​

Test whether a string is a valid integer.

Type:

(string) -> bool

Arguments:

  • (unlabeled) (of type string)

string.length​

Return the string's length using the given encoding. Raises error.invalid on errors.

Type:

(?encoding : string?, string) -> int

Arguments:

  • encoding (of type string?, which defaults to null): Encoding used to split characters. Should be one of: "utf8" or "ascii"
  • (unlabeled) (of type string)

string.lowercase​

Convert a string to lowercase.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.make​

Create a string of a given length using the given character.

Type:

(?char_code : int, int) -> string

Arguments:

  • char_code (of type int, which defaults to 32): Character code.
  • (unlabeled) (of type int): String length.

string.match​

Match a string with an expression. Perl compatible regular expressions are recognized. Hence, special characters should be escaped. Alternatively, one can use the the r/_/.test(_) syntax for regular expressions.

Type:

(pattern : string, string) -> bool

Arguments:

  • pattern (of type string)
  • (unlabeled) (of type string)

string.nth​

Retrieve a character in a string. Raises error.not_found if character does not exist.

Type:

(string, int) -> int

Example:

c = string.nth("abcde", 2)
print(c) # should print 99 which is the ascii code for "c"

Arguments:

  • (unlabeled) (of type string): String to look into.
  • (unlabeled) (of type int): Index of the character.

string.null_terminated​

Add a null character at the end of a string.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string): String.

string.of_int​

Convert an int to string.

Type:

(?digits : int, 'a) -> string

Arguments:

  • digits (of type int, which defaults to 0): Minimal number of digits (pad with 0s on the left if necessary).
  • (unlabeled) (of type 'a)

string.quote​

Return a quoted copy of the given string. By default, the string is assumed to be "utf8" encoded and is escaped following JSON and javascript specification.

Type:

(?encoding : string?, string) -> string

Arguments:

  • encoding (of type string?, which defaults to null): One of: "ascii" or "utf8". If null, utf8 is tried first and ascii is used as a fallback if this fails.
  • (unlabeled) (of type string)

string.recode​

Convert a string. Effective only if Camomile is enabled.

Type:

(?in_enc : string?, ?out_enc : string, string) -> string

Arguments:

  • in_enc (of type string?, which defaults to null): Input encoding. Autodetected if null.
  • out_enc (of type string, which defaults to "UTF-8"): Output encoding.
  • (unlabeled) (of type string)

string.replace​

Replace all substrings matched by a pattern by another string returned by a function. Alternatively, one can use the r/_/g.replace(_) syntax for regular expressions.

Type:

(pattern : string, ((string) -> string), string) -> string

Arguments:

  • pattern (of type string): Pattern (regular expression) of substrings which should be replaced.
  • (unlabeled) (of type (string) -> string): Function getting a matched substring an returning the string to replace it with.
  • (unlabeled) (of type string): String whose substrings should be replaced.

string.residual​

What remains of a string after a given prefix.

Type:

(?encoding : string?, prefix : string, string) -> string?

Arguments:

  • encoding (of type string?, which defaults to null): Encoding used to split characters. Should be one of: "utf8" or "ascii"
  • prefix (of type string): Requested prefix.
  • (unlabeled) (of type string)

string.spaces​

Generate a given number of spaces (this can be useful for indenting).

Type:

(int) -> string

Arguments:

  • (unlabeled) (of type int): Number of spaces.

string.split​

Split a string at "separator". Perl compatible regular expressions are recognized. Hence, special characters should be escaped. Alternatively, one can use the r/_/.split(_) syntax for regular expressions.

Type:

(separator : string, string) -> [string]

Arguments:

  • separator (of type string)
  • (unlabeled) (of type string)

string.split.first​

Split a string in two at first "separator".

Type:

(?encoding : string?, separator : string, string) -> string * string

Arguments:

  • encoding (of type string?, which defaults to null)
  • separator (of type string)
  • (unlabeled) (of type string)

string.sub​

Get a substring of a string. Returns "" if no such substring exists.

Type:

(string, start : int, ?encoding : string?, length : int) -> string

Arguments:

  • (unlabeled) (of type string)
  • start (of type int): Return a sub string starting at this position. First position is 0.
  • encoding (of type string?, which defaults to null): Encoding used to split characters. Should be one of: "utf8" or "ascii"
  • length (of type int): Return a sub string of length characters.

string.to_float​

Convert a string to a float.

Type:

(?default : float, string) -> float

Arguments:

  • default (of type float, which defaults to 0.0)
  • (unlabeled) (of type string)

string.to_int​

Convert a string to a int.

Type:

(?default : int, string) -> int

Arguments:

  • default (of type int, which defaults to 0)
  • (unlabeled) (of type string)

string.trim​

Return a string without leading and trailing whitespace.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.unescape​

This function is the inverse of string.escape.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.unquote​

Return an unquoted copy of the given string. Quotes are removed by trying to parse the string following the JSON string escaping convention.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string.uppercase​

Convert a string to uppercase.

Type:

(string) -> string

Arguments:

  • (unlabeled) (of type string)

string_of_metadata​

Standard function for displaying metadata. Shows artist and title, using "Unknown" when a field is empty.

Type:

([string * string]) -> string

Arguments:

  • (unlabeled) (of type [string * string]): Metadata packet to be displayed.

url.decode​

Decode an encoded url (e.g. "%20" becomes " ").

Type:

(?plus : bool, string) -> string

Arguments:

  • plus (of type bool, which defaults to true)
  • (unlabeled) (of type string)

url.encode​

Encode an url (e.g. " " becomes "%20").

Type:

(?plus : bool, string) -> string

Arguments:

  • plus (of type bool, which defaults to true)
  • (unlabeled) (of type string)

url.split​

Split an url of the form foo?arg=bar&arg2=bar2 into ("foo",[("arg","bar"),("arg2","bar2")]). The returned strings are decoded (see url.decode).

Type:

(string) -> string * [string * string]

Arguments:

  • (unlabeled) (of type string): Url to split.

url.split_args​

Split the arguments of an url of the form arg=bar&arg2=bar2 into [("arg","bar"),("arg2","bar2")]. The returned strings are decoded (see url.decode).

Type:

(string) -> [string * string]

Arguments:

  • (unlabeled) (of type string): Argument string to split.

xml.stringify​

Convert a value to XML. If the value cannot be represented as XML (for instance a function), a error.xml exception is raised.

Type:

(?compact : bool, 'a) -> string

Arguments:

  • compact (of type bool, which defaults to false): Output compact text.
  • (unlabeled) (of type 'a)

yaml.stringify​

Convert a value to YAML. If the value cannot be represented as YAML (for instance a function), a error.yaml exception is raised.

Type:

(?scalar_style : string, ?layout_style : string, 'a) -> string

Arguments:

  • scalar_style (of type string, which defaults to "any"): Scalar style. One of: "any", "plain", "single_quoted", "double_quoted", "literal" or "folded".
  • layout_style (of type string, which defaults to "any"): Layout style. One of: "any", "block" or "flow".
  • (unlabeled) (of type 'a)