Trait pest::Parser
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[src]
pub trait Parser<'a, T: Input<'a>> { type Rule; type Token; fn input(&self) -> &T; fn input_mut(&mut self) -> &mut T; fn try<F>(&mut self, revert: bool, rule: F) -> bool where F: FnOnce(&mut Self) -> bool; fn prec_climb<F, G>(&mut self, pos: usize, left: usize, min_prec: u8, last_op: Option<(Option<Self::Rule>, u8, bool)>, primary: &mut F, climb: &mut G) -> (Option<(Option<Self::Rule>, u8, bool)>, Option<usize>) where F: FnMut(&mut Self) -> bool, G: FnMut(&mut Self) -> Option<(Option<Self::Rule>, u8, bool)>; fn end(&self) -> bool; fn eoi_matched(&self) -> bool; fn reset(&mut self); fn queue(&self) -> &Vec<Self::Token>; fn queue_mut(&mut self) -> &mut Vec<Self::Token>; fn queue_index(&self) -> usize; fn inc_queue_index(&self); fn set_queue_index(&self, index: usize); fn skip_ws(&mut self); fn skip_com(&mut self); fn is_atomic(&self) -> bool; fn set_atomic(&mut self, value: bool); fn track(&mut self, failed: Self::Rule, pos: usize); fn tracked_len(&self) -> usize; fn expected(&mut self) -> (Vec<Self::Rule>, usize); }
A trait
that defines a parser.
Associated Types
Required Methods
fn input(&self) -> &T
fn input_mut(&mut self) -> &mut T
fn try<F>(&mut self, revert: bool, rule: F) -> bool where F: FnOnce(&mut Self) -> bool
Tries to match rule
, returns whether it matched, and advances a parser with in case it
did. If revert
is true
, the parser will not advance.
fn prec_climb<F, G>(&mut self, pos: usize, left: usize, min_prec: u8, last_op: Option<(Option<Self::Rule>, u8, bool)>, primary: &mut F, climb: &mut G) -> (Option<(Option<Self::Rule>, u8, bool)>, Option<usize>) where F: FnMut(&mut Self) -> bool, G: FnMut(&mut Self) -> Option<(Option<Self::Rule>, u8, bool)>
Uses the precendence climbing algorithm to match rules. pos
is the current position
of the queue. left
is the left-most starting position of the current rule. min_prec
is
the currently processed precedence. last_op
is the last greedily parsed infix operator.
primary
is a closure defined in grammar!
that parses a primary expression. climb
is a
closure defined in grammar!
that returns the first Rule
that was parsed (provided it
was not silented) along with its precedence and right-associativity, or None
if no
operator passes. This operator triplet is also returned by the function when it greedily
parses an operator useful for a higher precedence.
fn end(&self) -> bool
Returns whether a Parser
has reached its end.
fn eoi_matched(&self) -> bool
Returns whether a Parser
has matched end-of-input.
fn reset(&mut self)
Reset a Parser
.
fn queue(&self) -> &Vec<Self::Token>
Returns the queue of all matched Token
s.
fn queue_mut(&mut self) -> &mut Vec<Self::Token>
Returns the mutable queue of all matched Token
s.
fn queue_index(&self) -> usize
Returns the current index within the queue. Used in process!
.
fn inc_queue_index(&self)
Increments the current index within the queue. Used in process!
.
fn set_queue_index(&self, index: usize)
Set the current index within the queue. Used in process!
.
fn skip_ws(&mut self)
Skips white-space.
fn skip_com(&mut self)
Skips comments.
fn is_atomic(&self) -> bool
Returns whether a Parser
is currently inside an atomic rule.
fn set_atomic(&mut self, value: bool)
Sets a Parser
to atomic rule mode, barring comment & white-space skipping.
fn track(&mut self, failed: Self::Rule, pos: usize)
Keeps track of rule failures. It gets called when a Rule
fails at pos
.
fn tracked_len(&self) -> usize
Returns the length of the tracked Rule
s.
fn expected(&mut self) -> (Vec<Self::Rule>, usize)
Retuns a Vec
of all expected Rule
s at the deepest position where the parsing last
stopped. It only returns leafs from the rule tree. Used for error reporting.