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JsonPointer

Helpers for escaping and unescaping JSON Pointer path segments. JSON Pointer uses / to separate path tokens inside a JSON document, so token text must encode literal ~ and / characters. This module provides the two RFC 6901 token conversions used by JSON Patch and related path handling.

2 exports Added in v4.0.0 Source

Decoding

unescapeToken

Added in v4.0.0 Source

Decodes a JSON Pointer reference token according to RFC 6901 escaping rules.

When to use

Use when you need to decode a single escaped JSON Pointer path segment.

Details

  • Returns a new unescaped string
  • Replaces ~1 with / (forward slash) and ~0 with ~ (tilde)
  • Returns the input unchanged if it contains no escaped sequences
  • Empty strings are valid and returned unchanged

Gotchas

The replacement order matters: ~1 is replaced before ~0 to prevent incorrect decoding.

See

  • escapeToken The inverse operation for encoding tokens

Signature

declare function unescapeToken(token: string): string

Example

(Unescaping special characters)

import { JsonPointer } from "effect"


JsonPointer.unescapeToken("a~1b") // => "a/b"
JsonPointer.unescapeToken("c~0d") // => "c~d"
JsonPointer.unescapeToken("path~1to~0key") // => "path/to~key"

Encoding

escapeToken

Added in v4.0.0 Source

Escapes a JSON Pointer reference token according to RFC 6901 by encoding special characters so the token can be safely used as a segment in a JSON Pointer.

When to use

Use when you need to escape a single JSON Pointer path segment.

Details

  • Returns a new escaped string
  • Replaces ~ (tilde) with ~0 and / (forward slash) with ~1
  • Returns the input unchanged if it contains no special characters
  • Empty strings are valid and returned unchanged

Gotchas

The replacement order matters: ~ is replaced before / to prevent double-escaping.

See

  • unescapeToken The inverse operation for decoding escaped tokens

Signature

declare function escapeToken(token: string): string

Example

(Escaping special characters)

import { JsonPointer } from "effect"


JsonPointer.escapeToken("a/b") // => "a~1b"
JsonPointer.escapeToken("c~d") // => "c~0d"
JsonPointer.escapeToken("path/to~key") // => "path~1to~0key"