Text

Use this when concatenating, formatting, splitting, searching, or matching strings.

Core operations

Function	Signature	Description	Example
cat	t t > t	Concatenate two strings	cat "hello" " world" -> "hello world"
len	t > n	String length	len "hello" -> 5
trm	t > t	Trim whitespace	trm " hi " -> "hi"
spl	t t > L t	Split string by delimiter	spl "a,b,c" "," -> ["a","b","c"]
has	t t > b	Check if string contains substring	has "hello" "ell" -> true

Regex

Function	Signature	Description	Example
rgx	t t > L t	Regex match (returns captures)	rgx "abc123" "[0-9]+" -> ["123"]
rgxall	t t > L (L t)	All matches with captures, one inner list per match. With no capture groups, each inner list holds the whole match.	rgxall "(\\w+)=(\\d+)" "a=1 b=2" -> [["a","1"],["b","2"]]
rgxall1	t t > L t	All matches of a single-group pattern, flattened. With no capture groups, returns the list of whole matches. Errors at verify-time if the pattern has 2+ capture groups, use rgxall instead.	rgxall1 "(\\d+)" "a=1 b=2" -> ["1","2"]

Formatting

Function	Signature	Description	Example
fmt	t ... > t	Format string with values	fmt "{} is {}" "sky" "blue"

fmt is pure-functional sprintf, not print. A bare fmt "..." v statement is silently discarded on every engine. Use prnt fmt "..." v to print or line=fmt "..." v to capture. The verifier emits ILO-T032 when fmt/fmt2 is a non-tail statement with no binding (tail position, e.g. f v:n>t;fmt "x={}" v, is the documented “return formatted text” idiom and does not warn).

Conversion

Function	Signature	Description	Example
str	_ > t	Convert any value to string	str 42 -> "42"
num	t > n	Parse string to number	num "42" -> 42

Output

Function	Signature	Description	Example
prnt	_ > _	Print value and return it	prnt "hello"

Aliases

Long form	Short form
concat	cat
length	len
trim	trm
split	spl
contains	has
format	fmt
regex	rgx
print	prnt