lang

Language primitives: string, number, bytes, array, and boolean helpers for data manipulation. Requires load lang (import the helpers you use, e.g. load lang [@map @filter], or qualify them as @lang:map).

load lang

Helpers

Helper	Returns	Description
@lang:all	bool	Whether every element satisfies the predicate.
@lang:any	bool	Whether at least one element satisfies the predicate.
@lang:at	any	Access an element by index in an array.
@lang:bytes.at	bytes	Access a single byte by index in a bytes value.
@lang:bytes.concat	bytes	Concatenate bytes values together.
@lang:bytes.len	number	Byte length of a bytes value (a UTF-8 character may span several bytes).
@lang:bytes.not	bytes	Bitwise NOT of a bytes value (256-bit complement).
@lang:bytes.slice	bytes	Extract a byte range from a bytes value.
@lang:concat	array	Concatenate arrays together.
@lang:enumerate	array	Pair every element of an array with its index.
@lang:filter	array	Keep elements of an array for which a helper returns truthy.
@lang:find	any	First element that satisfies the predicate; no match is an error.
@lang:flat	array	Flatten one level of nesting in an array.
@lang:includes	bool	Check whether an array contains an element.
@lang:keys	array	Entry names of a record ([a:1 b:2] or [name value] pairs), as an array.
@lang:len	number	Length of a value: element count for an array, byte length for a string or bytes.
@lang:lookup	any	Look up an entry by name in a record ([a:1 b:2] or [name value] pairs).
@lang:map	array	Transform each element of an array by applying a helper.
@lang:num.format	string	Format an integer in base units as ordinary decimal notation, trimming trailing fractional zeros.
@lang:num.parse	number	Parse ordinary decimal notation into base units with explicit rounding and signedness.
@lang:reduce	any	Reduce an array to a single value by applying a helper.
@lang:reverse	array	Reverse the order of an array's elements.
@lang:slice	array	Extract a section of an array.
@lang:sort	array	Sort an array: ascending by default, desc for descending, or by a comparator helper.
@lang:str.at	string	Access one UTF-8 byte as a string; reject bytes belonging to multibyte characters.
@lang:str.charset	bool	Check whether every byte of a string is in a character class (ranges like a-z0-9-; a leading or trailing dash is the literal -).
@lang:str.concat	string	Concatenate strings together.
@lang:str.includes	bool	Check whether a string contains a substring (exact byte sequence, case-sensitive).
@lang:str.join	string	Join array elements into a string with a delimiter.
@lang:str.len	number	Length of a string in UTF-8 bytes.
@lang:str.lower	string	Convert ASCII letters in a string to lowercase; preserve other characters.
@lang:str.replace	string	Replace all occurrences of a substring (every non-overlapping left-to-right match).
@lang:str.slice	string	Extract a UTF-8 byte range, with clamped indexes and complete characters.
@lang:str.split	array | string	Split a string by a delimiter into an array of strings, or select one segment when an index is given.
@lang:str.upper	string	Convert ASCII letters in a string to uppercase; preserve other characters.
@lang:sum	number	Sum the elements of an array.
@lang:unique	array	Remove duplicates from an array, preserving first-occurrence order.
@lang:unzip	array	Transpose an array of pairs into two separate arrays.
@lang:values	array	Entry values of a record ([a:1 b:2] or [name value] pairs), as an array.
@lang:zip	array	Combine two arrays element-wise into an array of pairs.