View Source GenLSP.Structures.Position (gen_lsp v0.10.0)

Position in a text document expressed as zero-based line and character offset. Prior to 3.17 the offsets were always based on a UTF-16 string representation. So a string of the form a𐐀b the character offset of the character a is 0, the character offset of 𐐀 is 1 and the character offset of b is 3 since 𐐀 is represented using two code units in UTF-16. Since 3.17 clients and servers can agree on a different string encoding representation (e.g. UTF-8). The client announces it's supported encoding via the client capability general.positionEncodings. The value is an array of position encodings the client supports, with decreasing preference (e.g. the encoding at index 0 is the most preferred one). To stay backwards compatible the only mandatory encoding is UTF-16 represented via the string utf-16. The server can pick one of the encodings offered by the client and signals that encoding back to the client via the initialize result's property capabilities.positionEncoding. If the string value utf-16 is missing from the client's capability general.positionEncodings servers can safely assume that the client supports UTF-16. If the server omits the position encoding in its initialize result the encoding defaults to the string value utf-16. Implementation considerations: since the conversion from one encoding into another requires the content of the file / line the conversion is best done where the file is read which is usually on the server side.

Positions are line end character agnostic. So you can not specify a position that denotes | or | where | represents the character offset.

@since 3.17.0 - support for negotiated position encoding.

Link to this section Summary



  • line: Line position in a document (zero-based).

Link to this section Types

@type t() :: %GenLSP.Structures.Position{
  character: GenLSP.BaseTypes.uinteger(),
  line: GenLSP.BaseTypes.uinteger()

Link to this section Functions

Link to this function


View Source (struct)



  • line: Line position in a document (zero-based).

    If a line number is greater than the number of lines in a document, it defaults back to the number of lines in the document. If a line number is negative, it defaults to 0.

  • character: Character offset on a line in a document (zero-based).

    The meaning of this offset is determined by the negotiated PositionEncodingKind.

    If the character value is greater than the line length it defaults back to the line length.