Trait pest::inputs::Input

pub trait Input: Debug {
    fn len(&self) -> usize;
    fn is_empty(&self) -> bool;
    fn file_name(&self) -> Option<OsString>;
    unsafe fn slice(&self, start: usize, end: usize) -> &str;
    unsafe fn line_col(&self, pos: usize) -> (usize, usize);
    unsafe fn line_of(&self, pos: usize) -> &str;
    unsafe fn skip(&self, n: usize, pos: usize) -> Option<usize>;
    unsafe fn match_string(&self, string: &str, pos: usize) -> bool;
    unsafe fn match_insensitive(&self, string: &str, pos: usize) -> bool;
    unsafe fn match_range(
        &self, 
        range: Range<char>, 
        pos: usize
    ) -> Option<usize>;
}

A trait that defines an input for a Parser. It should be implemented by custom input sources as minimally and efficiently as possible. unsafe methods should not be called directly; in order to parse the Input manually use Position and ParserState.

Implementors should NOT introduce undefined behavior in these methods. Undefined behavior is acceptable ONLY when the positions are either out of bounds or don't match UTF-8 indices, since these cases are avoided by using the Position API.

Required Methods

fn len(&self) -> usize

Returns length of the input.

fn is_empty(&self) -> bool

Returns whether the input is empty.

fn file_name(&self) -> Option<OsString>

Returns the file name of the input or None in the case where it doesn't have one.

unsafe fn slice(&self, start: usize, end: usize) -> &str

Slices the input.

Safety

This method can cause undefined behavior when start or end are either out of bounds or don't match UTF-8 indices.

unsafe fn line_col(&self, pos: usize) -> (usize, usize)

Returns the line - and column number of the input at pos.

Safety

This method can cause undefined behavior when pos is either out of bounds or doesn't match UTF-8 indices.

unsafe fn line_of(&self, pos: usize) -> &str

Returns the line of the input at pos.

Safety

This method can cause undefined behavior when pos is either out of bounds or doesn't match UTF-8 indices.

unsafe fn skip(&self, n: usize, pos: usize) -> Option<usize>

Tries to skip n chars at pos. Returns Some(len) with the UTF-8 length of the skipped chars position or None if there are not enough chars left to skip.

Safety

This method can cause undefined behavior when pos is either out of bounds or doesn't match UTF-8 indices.

unsafe fn match_string(&self, string: &str, pos: usize) -> bool

Matches string at pos and returns whether it matched.

Safety

This method can cause undefined behavior when pos is either out of bounds or doesn't match UTF-8 indices.

unsafe fn match_insensitive(&self, string: &str, pos: usize) -> bool

Matches string at pos case insensitively and returns whether it matched.

Safety

This method can cause undefined behavior when pos is either out of bounds or doesn't match UTF-8 indices.

unsafe fn match_range(&self, range: Range<char>, pos: usize) -> Option<usize>

Matches if the char is within the range and returns Some(len) with the matching char's UTF-8 length if it matched or None otherwise.

Safety

This method can cause undefined behavior when pos is either out of bounds or doesn't match UTF-8 indices.

Implementors

• impl Input for FileInput
• impl Input for StringInput