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 parameters:
- B
The desired result type
- Value parameters:
- 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 parameters:
- B
The desired result type
- Value parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- 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 parameters:
- p
The parser to perform
- Returns:
The result of the parser
p, if any- Since:
3.2.0