This class is used to index registers within the mutable state. Currently, there are only 4 available registers, so use them wisely!
If you need more than four registers but know that they will be used
at different times you can rename your register, as long as they point
to the same reference. You may find the
Parsley[A].cast[B: ClassTag]: Parsley[B]
combinator useful to change the type of a Reg[Any].
- Since
2.2.0
- Note
It is undefined behaviour to use a register in multiple different independent parsers. You should be careful to parameterise the registers in shared parsers and allocate fresh ones for each "top-level" parser you will run.
- Companion
- object
Value members
Concrete methods
Consumes no input and returns the value stored in this register
Consumes no input and returns the value stored in this register
- Returns
The value stored in register
- Since
3.2.0
Consumes no input and returns the value stored in this register after applying a function.
Consumes no input and returns the value stored in this register after applying a function.
- Type Params
- B
The desired result type
- Value Params
- f
The function used to transform the value in this register
- Returns
The value stored in this register applied to
f- Since
3.2.0
Returns the value stored this register after applying a function obtained from given parser.
Returns the value stored this register after applying a function obtained from given parser.
- Type Params
- B
The desired result type
- Value Params
- pf
The parser which provides the function to transform values
- Returns
The value stored in this register applied to
ffrompf- Since
3.2.0
- Note
The value is fetched after
pfis executed
For the duration of parser p the state stored in this register is instead set to x. The change is undone
after p has finished.
For the duration of parser p the state stored in this register is instead set to x. The change is undone
after p has finished.
- Value Params
- p
The parser to execute with the adjusted state
- x
The value to place into this register
- Returns
The parser that performs
pwith the modified state- Since
3.2.0
For the duration of parser q the state stored in this register is instead set to the return value of p. The
change is undone after q has finished.
For the duration of parser q the state stored in this register is instead set to the return value of p. The
change is undone after q has finished.
- Value Params
- p
The parser whose return value is placed in this register
- q
The parser to execute with the adjusted state
- Returns
The parser that performs
qwith the modified state- Since
3.2.0
For the duration of parser p the state stored in this register is instead modified with f. The change is undone
after p has finished.
For the duration of parser p the state stored in this register is instead modified with f. The change is undone
after p has finished.
- Value Params
- f
The function used to modify the value in this register
- p
The parser to execute with the adjusted state
- Returns
The parser that performs
pwith the modified state- Since
3.2.0
Modifies the value contained in this register using function f.
Modifies the value contained in this register using function f.
- Value Params
- f
The function used to modify the register
- Since
3.2.0
Modifies the value contained in this register using function f obtained from executing p.
Modifies the value contained in this register using function f obtained from executing p.
- Value Params
- f
The function used to modify the register
- Since
3.2.0
- Note
The value is modified after
pfis executed
Consumes no input and places the value x into this register.
Consumes no input and places the value x into this register.
- Value Params
- x
The value to place in the register
- Since
3.2.0
Places the result of running p into this register.
Places the result of running p into this register.
- Value Params
- p
The parser to derive the value from
- Since
3.2.0
Places the result of running p into this register.
Places the result of running p into this register.
- Value Params
- f
A function which adapts the result of
pso that it can fit inr- p
The parser to derive the value from
- Since
3.0.0
rollback(reg, p) will perform p, but if it fails without consuming input, any changes to this register will
be reverted.
rollback(reg, p) will perform p, but if it fails without consuming input, any changes to this register will
be reverted.
- Value Params
- p
The parser to perform
- Returns
The result of the parser
p, if any- Since
3.2.0