📝 String Operations

Module: str/* | Operators: 26

Text manipulation including formatting, splitting, trimming, and templating.

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Operator Reference

str/len

Length · 1 argument · returns number

String length

Parameter	Type	Description
s	string	The string

(str/len "hello") // => 5

str/upper

Upper · 1 argument · returns string

Convert to uppercase

Parameter	Type	Description
s	string	The string

(str/upper "hello") // => "HELLO"

str/lower

Lower · 1 argument · returns string

Convert to lowercase

Parameter	Type	Description
s	string	The string

(str/lower "HELLO") // => "hello"

str/trim

Trim · 1 argument · returns string

Remove leading and trailing whitespace

Parameter	Type	Description
s	string	The string

(str/trim " hello ") // => "hello"

str/trimStart

Trim Start · 1 argument · returns string

Remove leading whitespace

Parameter	Type	Description
s	string	The string

(str/trimStart " hello") // => "hello"

str/trimEnd

Trim End · 1 argument · returns string

Remove trailing whitespace

Parameter	Type	Description
s	string	The string

(str/trimEnd "hello ") // => "hello"

str/split

Split · 2 arguments · returns array

Split string into array by delimiter

Parameter	Type	Description
s	string	The string
delim	string	Delimiter

(str/split "a,b,c" ",") // => ["a", "b", "c"]

str/join

Join · 2 arguments · returns string

Join array elements into string

Parameter	Type	Description
arr	array	Array to join
delim	string	Delimiter

(str/join (a "b" "c") ", ") // => "a, b, c"

str/slice

Slice · 2–3 arguments · returns string

Extract substring

Parameter	Type	Description
s	string	The string
start	number	Start index
end	number	End index (exclusive)

(str/slice "hello" 1 4) // => "ell"

str/replace

Replace · 3 arguments · returns string

Replace first occurrence

Parameter	Type	Description
s	string	The string
find	string	String to find
replace	string	Replacement

(str/replace "hello world" "world" "there") // => "hello there"

str/replaceAll

Replace All · 3 arguments · returns string

Replace all occurrences

Parameter	Type	Description
s	string	The string
find	string	String to find
replace	string	Replacement

(str/replaceAll "a-b-c" "-" "_") // => "a_b_c"

str/includes

Includes · 2 arguments · returns boolean

Check if string contains substring

Parameter	Type	Description
s	string	The string
search	string	Substring to find

(str/includes "hello world" "world") // => true

str/startsWith

Starts With · 2 arguments · returns boolean

Check if string starts with prefix

Parameter	Type	Description
s	string	The string
prefix	string	Prefix to check

(str/startsWith "hello" "hel") // => true

str/endsWith

Ends With · 2 arguments · returns boolean

Check if string ends with suffix

Parameter	Type	Description
s	string	The string
suffix	string	Suffix to check

(str/endsWith "hello" "lo") // => true

str/padStart

Pad Start · 2–3 arguments · returns string

Pad string from start to target length

Parameter	Type	Description
s	string	The string
len	number	Target length
char	string	Padding character

(str/padStart "5" 3 "0") // => "005"

str/padEnd

Pad End · 2–3 arguments · returns string

Pad string from end to target length

Parameter	Type	Description
s	string	The string
len	number	Target length
char	string	Padding character

(str/padEnd "5" 3 "0") // => "500"

str/repeat

Repeat · 2 arguments · returns string

Repeat string n times

Parameter	Type	Description
s	string	The string
count	number	Repeat count

(str/repeat "ab" 3) // => "ababab"

str/reverse

Reverse · 1 argument · returns string

Reverse string

Parameter	Type	Description
s	string	The string

(str/reverse "hello") // => "olleh"

str/capitalize

Capitalize · 1 argument · returns string

Capitalize first character

Parameter	Type	Description
s	string	The string

(str/capitalize "hello") // => "Hello"

str/titleCase

Title Case · 1 argument · returns string

Convert to Title Case

Parameter	Type	Description
s	string	The string

(str/titleCase "hello world") // => "Hello World"

str/camelCase

Camel Case · 1 argument · returns string

Convert to camelCase

Parameter	Type	Description
s	string	The string

(str/camelCase "hello world") // => "helloWorld"

str/kebabCase

Kebab Case · 1 argument · returns string

Convert to kebab-case

Parameter	Type	Description
s	string	The string

(str/kebabCase "Hello World") // => "hello-world"

str/snakeCase

Snake Case · 1 argument · returns string

Convert to snake_case

Parameter	Type	Description
s	string	The string

(str/snakeCase "Hello World") // => "hello_world"

str/default

Default · 2 arguments · returns string

Return default if value is null/undefined/empty

Parameter	Type	Description
s	string | null	The value
default	string	Default value

(str/default null "N/A") // => "N/A"

str/template

Template · 2 arguments · returns string

Variable substitution in template string

Parameter	Type	Description
template	string	Template with {placeholders}
vars	object	Variables to substitute

(str/template "Hello, {name}!" {"name": "World"}) // => "Hello, World!"

str/truncate

Truncate · 2–3 arguments · returns string

Truncate string with optional suffix

Parameter	Type	Description
s	string	The string
len	number	Maximum length
suffix	string	Suffix for truncated strings

(str/truncate "Hello World" 8 "...") // => "Hello..."