Text Format

Canonical document

ikv2 "player_save"
{
    "title" "iKv demo"
    "version" 2
    "enabled" true
    "speed" 12.5
    "player" {
        "name" "Ada"
        "note" "line one\nline two"
    }
    "inventory" [
        "wrench"
        "battery"
        "map"
    ]
}

The normal header is:

ikv<version> <root-name>

The root name may be quoted or a bare word when parsing. Writers always emit a quoted name and use "root" if the in-memory root name is empty.

Informal grammar

document      := versioned-object | object | plain-members
versioned-object := ("ikv1" | "ikv2") root-name object
object        := "{" { member [","] } "}"
member        := quoted-string value
array         := "[" { value [","] } "]"
value         := object | array | quoted-string | word
root-name     := quoted-string | word
plain-members := { member [","] }

Commas are optional between object members and array elements. Whitespace separates adjacent values.

Keys and strings

Object keys must be quoted strings. Supported escapes are:

Escape	Result
`\\`	Backslash
`\"`	Double quote
`\n`	Newline
`\r`	Carriage return
`\t`	Tab

Other backslash sequences are retained literally rather than interpreted as Unicode or hexadecimal escapes. The current format does not implement \uXXXX escapes.

Bare-word inference

Unquoted words are interpreted in this order:

true or false → boolean
null → null
A complete numeric token containing ., e, or E → float
A complete base-10 numeric token → signed integer
Anything else → string

Examples:

{
    "a" true
    "b" -42
    "c" 6.25
    "d" 1e6
    "e" unquoted-string
}

Writers quote all strings, so generated files do not rely on bare-string inference.

Comments

Two line-comment forms are supported outside strings:

// C++ style comment
# shell style comment

Each runs through the end of the line. Block comments are not supported.

Alternate accepted roots

The parser also accepts an unversioned braced object:

{
    "name" "demo"
}

Or plain top-level members:

"name" "demo"
"count" 3

Versioned output is recommended because it is explicit and is what the writer produces for object roots.

Formatting behavior

Writers indent nested values by four spaces.
Floating-point values use up to 17 significant digits.
Arrays and objects are written over multiple lines.
Object member order is not guaranteed.
An object root receives a version header; a non-object C root is written as a bare value.

Text Format

Canonical document

Informal grammar

Keys and strings

Bare-word inference

Comments

Alternate accepted roots

Formatting behavior

iKvxx Wiki

Format Reference

C++ API

Development