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Strings

Strings in Aether are UTF-8 sequences. They support indexing, slicing, interpolation, multi-line literals, and a set of built-in methods.

Literals

let s = "Hello, World"
let s = 'single quotes work too'

Multi-line strings use triple quotes — content is taken verbatim, including newlines and embedded quotes:

let body = """
{
    "name": "Alice",
    "role": "admin"
}
"""

Concatenation

let greeting = "Hello" + " " + "World"   // Hello World

Interpolation

Embed any expression inside ${}:

let name = "Alice"
let age = 30
println("${name} is ${age} years old")       // Alice is 30 years old
println("Sum: ${1 + 2 + 3}")                 // Sum: 6
println("Score: ${user["score"]} points")    // dict access in interpolation

Indexing

Access a character by position. Negative indices count from the end. Out-of-bounds returns an empty string.

let s = "Hello"
s[0]    // "H"
s[4]    // "o"
s[-1]   // "o" (last character)
s[-2]   // "l"
s[99]   // "" (out of bounds)

Slicing

Extract a substring with [start:end]. Either end is optional (defaults to start/end of string).

let s = "Hello World"
s[0:5]    // "Hello"
s[6:11]   // "World"
s[6:]     // "World"  (to end)
s[:5]     // "Hello"  (from start)
s[:]      // "Hello World"  (full copy)
s[-5:]    // "World"  (last 5 chars)
s[:-6]    // "Hello"  (all but last 6)

Methods

Method Returns
s.upper() uppercase copy
s.lower() lowercase copy
s.trim() whitespace stripped from both ends
s.split(sep) array of substrings
s.length character count (also len(s)) 
"Hello World".upper()      // "HELLO WORLD"
"  hello  ".trim()         // "hello"
"a,b,c".split(",")         // ["a", "b", "c"]
"Hello".length             // 5

Examples

Extract domain from email

fn domain(email) {
    let parts = email.split("@")
    return parts[1]
}
println(domain("user@example.com"))  // example.com

Reverse a string

fn reverse(s) {
    let result = ""
    for i in range(len(s) - 1, -1) {
        result = result + s[i]
    }
    return result
}

Format a name

fn last_first(full) {
    let parts = full.split(" ")
    return "${parts[1]}, ${parts[0]}"
}
println(last_first("Alice Johnson"))  // Johnson, Alice

Limitations

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