GHC.Data.StringBuffer

A StringBuffer is an internal pointer to a sized chunk of bytes. The bytes are intended to be *immutable*. There are pure operations to read the contents of a StringBuffer.

A StringBuffer may have a finalizer, depending on how it was obtained.

Read a file into a StringBuffer. The resulting buffer is automatically managed by the garbage collector.

Encode a String into a StringBuffer as UTF-8. The resulting buffer is automatically managed by the garbage collector.

Convert a UTF-8 encoded ByteString into a 'StringBuffer. This really relies on the internals of both ByteString and StringBuffer.

O(n) (but optimized into a memcpy by bytestring under the hood)

Return the first UTF-8 character of a nonempty StringBuffer and as well the remaining portion (analogous to uncons). Warning: The behavior is undefined if the StringBuffer is empty. The result shares the same buffer as the original. Similar to utf8DecodeChar, if the character cannot be decoded as UTF-8, '\0' is returned.

Return the first UTF-8 character of a nonempty StringBuffer (analogous to head). Warning: The behavior is undefined if the StringBuffer is empty. Similar to utf8DecodeChar, if the character cannot be decoded as UTF-8, '\0' is returned.

Check whether a StringBuffer is empty (analogous to Data.List.null).

Computes a hash of the contents of a StringBuffer.

Return a StringBuffer with the first UTF-8 character removed (analogous to tail). Warning: The behavior is undefined if the StringBuffer is empty. The result shares the same buffer as the original.

Return a StringBuffer with the first n bytes removed. Warning: If there aren't enough characters, the returned StringBuffer will be invalid and any use of it may lead to undefined behavior. The result shares the same buffer as the original.

Compute the difference in offset between two StringBuffers that share the same buffer. Warning: The behavior is undefined if the StringBuffers use separate buffers.

Computes a StringBuffer which points to the first character of the wanted line. Lines begin at 1.

Decode the first n bytes of a StringBuffer as UTF-8 into a String. Similar to utf8DecodeChar, if the character cannot be decoded as UTF-8, they will be replaced with '\0'.

Return the previous n characters (or fewer if we are less than n characters into the buffer.

Returns true if the buffer contains Unicode bi-directional formatting characters.

https://www.unicode.org/reports/tr9/#Bidirectional_Character_Types

Bidirectional format characters are one of 'x202a' : "U+202A LEFT-TO-RIGHT EMBEDDING (LRE)" 'x202b' : "U+202B RIGHT-TO-LEFT EMBEDDING (RLE)" 'x202c' : "U+202C POP DIRECTIONAL FORMATTING (PDF)" 'x202d' : "U+202D LEFT-TO-RIGHT OVERRIDE (LRO)" 'x202e' : "U+202E RIGHT-TO-LEFT OVERRIDE (RLO)" 'x2066' : "U+2066 LEFT-TO-RIGHT ISOLATE (LRI)" 'x2067' : "U+2067 RIGHT-TO-LEFT ISOLATE (RLI)" 'x2068' : "U+2068 FIRST STRONG ISOLATE (FSI)" 'x2069' : "U+2069 POP DIRECTIONAL ISOLATE (PDI)"

This list is encoded in bidirectionalFormatChars