position
This module contains parsers that provide a way to extract position information during a parse.
Position parsers can be important for when the final result of the parser needs to encode position information for later consumption: this is particularly useful for abstract syntax trees. Offset is also exposed by this interface, which may be useful for establishing a caret size in specialised error messages.
Attributes
- Since:
4.2.0
- Source:
- position.scala
- Graph
- Supertypes
- Self type
- position.type
Members list
pos
This parser returns the current column number (starting at 1) of the input without having any other effect.
This parser returns the current column number (starting at 1) of the input without having any other effect.
When this combinator is ran, no input is required, nor consumed, and the current column number will always be successfully returned. It has no other effect on the state of the parser.
Attributes
- Returns:
a parser that returns the column number the parser is currently at.
- Note:
in the presence of wide unicode characters, the value returned may be inaccurate.
- Example:
scala> import parsley.position.col, parsley.character.char scala> col.parse("") val res0 = Success(1) scala> (char('a') *> col).parse("a") val res0 = Success(2) scala> (char('\n') *> col).parse("\n") val res0 = Success(1)- Source:
- position.scala
This parser returns the current line number (starting at 1) of the input without having any other effect.
This parser returns the current line number (starting at 1) of the input without having any other effect.
When this combinator is ran, no input is required, nor consumed, and the current line number will always be successfully returned. It has no other effect on the state of the parser.
Attributes
- Returns:
a parser that returns the line number the parser is currently at.
- Example:
scala> import parsley.position.line, parsley.character.char scala> line.parse("") val res0 = Success(1) scala> (char('a') *> line).parse("a") val res0 = Success(1) scala> (char('\n') *> line).parse("\n") val res0 = Success(2)- Source:
- position.scala
This parser returns the current line and column numbers (starting at 1) of the input without having any other effect.
This parser returns the current line and column numbers (starting at 1) of the input without having any other effect.
When this combinator is ran, no input is required, nor consumed, and the current line and column number will always be successfully returned. It has no other effect on the state of the parser.
Attributes
- Returns:
a parser that returns the line and column number the parser is currently at.
- Note:
in the presence of wide unicode characters, the column value returned may be inaccurate.
- Example:
scala> import parsley.position.pos, parsley.character.char scala> pos.parse("") val res0 = Success((1, 1)) scala> (char('a') *> pos).parse("a") val res0 = Success((1, 2)) scala> (char('\n') *> pos).parse("\n") val res0 = Success((2, 1))- Source:
- position.scala
Value members
Concrete fields
This parser returns the current offset into the input (starting at 0) without having any other effect.
This parser returns the current offset into the input (starting at 0) without having any other effect.
When this combinator is ran, no input is required, nor consumed, and the current offset into the input will always be successfully returned. It has no other effect on the state of the parser.
Attributes
- Returns:
a parser that returns the offset the parser is currently at.
- Note:
offset does not take wide unicode codepoints into account.
- Example:
scala> import parsley.position.offset, parsley.character.char scala> offset.parse("") val res0 = Success(0) scala> (char('a') *> offset).parse("a") val res0 = Success(1) scala> (char('\n') *> offset).parse("\n") val res0 = Success(1)- Source:
- position.scala