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#UTF-8

Encoding and decoding between strings and UTF-8 byte sequences.

#Encoding

Use encode to convert a string to UTF-8 bytes. Set bom=true to prepend the UTF-8 BOM (U+FEFF).

///|
test "encode" {
  let bytes = @utf8.encode("hi")
  inspect(bytes, content="b\"hi\"")
}

///|
test "encode_with_bom" {
  let bytes = @utf8.encode("hi", bom=true)
  inspect(bytes, content="b\"\\xef\\xbb\\xbfhi\"")
}

#Decoding

Use decode to convert UTF-8 bytes back to a string. Raises Malformed on invalid UTF-8 sequences. Set ignore_bom=true to strip a leading BOM if present.

///|
test "decode" {
  let bytes : Bytes = b"\x68\x69"
  let s = @utf8.decode(bytes)
  inspect(s, content="hi")
}

#Lossy Decoding

Use decode_lossy to decode bytes that may contain invalid UTF-8, replacing invalid sequences with the Unicode replacement character (U+FFFD).

///|
test "decode_lossy" {
  let bytes : Bytes = b"\x68\x80\x69"
  let s = @utf8.decode_lossy(bytes)
  inspect(s, content="h\u{FFFD}i")
}

#
Malformed

source
pub suberror Malformed {
  Malformed(BytesView)
} derive(
Debug)

Error type Malformed.

#
decode

source
fn decode(bytes : BytesView, ignore_bom? : Bool) -> String raise Malformed

Decode input bytes/text into structured output.

#
decode_lossy

source
fn decode_lossy(bytes : BytesView, ignore_bom? : Bool) -> String

References :
  • https://www.unicode.org/versions/Unicode16.0.0/core-spec/chapter-3/#G66453
  • https://www.unicode.org/versions/Unicode16.0.0/core-spec/chapter-5/#G40630

#
encode

source
fn encode(str : StringView, bom? : Bool) -> Bytes

Encodes a string into a UTF-8 byte array.

Panics if the string contains an invalid surrogate pair.

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