stri_enc_isutf8: Check If a Data Stream Is Possibly in UTF-8#

Description#

The function checks whether given sequences of bytes forms a proper UTF-8 string.

Usage#

stri_enc_isutf8(str)

Arguments#

str

character vector, a raw vector, or a list of raw vectors

Details#

FALSE means that a string is certainly not valid UTF-8. However, false positives are possible. For instance, (c4,85) represents (‘a with ogonek’) in UTF-8 as well as (‘A umlaut’, ‘Ellipsis’) in WINDOWS-1250. Also note that UTF-8, as well as most 8-bit encodings, extend ASCII (note that stri_enc_isascii implies that stri_enc_isutf8).

However, the longer the sequence, the greater the possibility that the result is indeed in UTF-8 – this is because not all sequences of bytes are valid UTF-8.

This function is independent of the way R marks encodings in character strings (see Encoding and stringi-encoding).

Value#

Returns a logical vector. Its i-th element indicates whether the i-th string corresponds to a valid UTF-8 byte sequence.

Author(s)#

Marek Gagolewski and other contributors

See Also#

The official online manual of stringi at https://stringi.gagolewski.com/

Gagolewski M., stringi: Fast and portable character string processing in R, Journal of Statistical Software 103(2), 2022, 1-59, doi:10.18637/jss.v103.i02

Other encoding_detection: about_encoding, stri_enc_detect2(), stri_enc_detect(), stri_enc_isascii(), stri_enc_isutf16be()

Examples#

stri_enc_isutf8(letters[1:3])
## [1] TRUE TRUE TRUE
stri_enc_isutf8('\u0105\u0104')
## [1] TRUE
stri_enc_isutf8('\u1234\u0222')
## [1] TRUE