Documentation
¶
Index ¶
- func Parse(filename string, b []byte, opts ...Option) (interface{}, error)
- func ParseFile(filename string, opts ...Option) (i interface{}, err error)
- func ParseReader(filename string, r io.Reader, opts ...Option) (interface{}, error)
- type Cloner
- type Condition
- type FieldOperator
- type Node
- type NodeOperator
- type NodeStack
- type Option
- func AllowInvalidUTF8(b bool) Option
- func Debug(b bool) Option
- func Entrypoint(ruleName string) Option
- func GlobalStore(key string, value interface{}) Option
- func InitState(key string, value interface{}) Option
- func MaxExpressions(maxExprCnt uint64) Option
- func Memoize(b bool) Option
- func Recover(b bool) Option
- func Statistics(stats *Stats, choiceNoMatch string) Option
- type Query
- type Stats
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
Types ¶
type Cloner ¶
type Cloner interface {
Clone() interface{}
}
Cloner is implemented by any value that has a Clone method, which returns a copy of the value. This is mainly used for types which are not passed by value (e.g map, slice, chan) or structs that contain such types.
This is used in conjunction with the global state feature to create proper copies of the state to allow the parser to properly restore the state in the case of backtracking.
type Condition ¶
type Condition struct {
Field string
Operator FieldOperator
Value any
Invert bool
}
Condition as struct
func (*Condition) HasWildcard ¶
HasWildcard checking if a condition contains a wildcard
type FieldOperator ¶
type FieldOperator string
FieldOperator as type
const ( NO FieldOperator = "" // equal EQ FieldOperator = "=" // equals LT FieldOperator = "<" // lesser than GT FieldOperator = ">" // greater than LE FieldOperator = "<=" // less or equal GE FieldOperator = ">=" // greater or equal NE FieldOperator = "!=" // not equal )
defining field operators
type Node ¶
type Node struct {
Operator NodeOperator
Conditions []any // could be a node or a condition
}
Node a implementation of a single node
type NodeOperator ¶
type NodeOperator string
NodeOperator defining as type
const ( NOOP NodeOperator = "NOP" ANDOP NodeOperator = "AND" OROP NodeOperator = "OR" )
some node operators
type NodeStack ¶
type NodeStack struct {
InvertGroup bool
// contains filtered or unexported fields
}
NodeStack stack of query nodes with conditions
var N NodeStack
N default nodestack
func (*NodeStack) CurrentCondition ¶
CurrentCondition getting the current condition, create new if not exists
func (*NodeStack) CurrentNode ¶
CurrentNode get the current node, create, if not set
func (*NodeStack) NewCondition ¶
NewCondition create a new condition and add it to the actual nodestack
type Option ¶
type Option func(*parser) Option
Option is a function that can set an option on the parser. It returns the previous setting as an Option.
func AllowInvalidUTF8 ¶
AllowInvalidUTF8 creates an Option to allow invalid UTF-8 bytes. Every invalid UTF-8 byte is treated as a utf8.RuneError (U+FFFD) by character class matchers and is matched by the any matcher. The returned matched value, c.text and c.offset are NOT affected.
The default is false.
func Debug ¶
Debug creates an Option to set the debug flag to b. When set to true, debugging information is printed to stdout while parsing.
The default is false.
func Entrypoint ¶
Entrypoint creates an Option to set the rule name to use as entrypoint. The rule name must have been specified in the -alternate-entrypoints if generating the parser with the -optimize-grammar flag, otherwise it may have been optimized out. Passing an empty string sets the entrypoint to the first rule in the grammar.
The default is to start parsing at the first rule in the grammar.
func GlobalStore ¶
GlobalStore creates an Option to set a key to a certain value in the globalStore.
func InitState ¶
InitState creates an Option to set a key to a certain value in the global "state" store.
func MaxExpressions ¶
MaxExpressions creates an Option to stop parsing after the provided number of expressions have been parsed, if the value is 0 then the parser will parse for as many steps as needed (possibly an infinite number).
The default for maxExprCnt is 0.
func Memoize ¶
Memoize creates an Option to set the memoize flag to b. When set to true, the parser will cache all results so each expression is evaluated only once. This guarantees linear parsing time even for pathological cases, at the expense of more memory and slower times for typical cases.
The default is false.
func Recover ¶
Recover creates an Option to set the recover flag to b. When set to true, this causes the parser to recover from panics and convert it to an error. Setting it to false can be useful while debugging to access the full stack trace.
The default is true.
func Statistics ¶
Statistics adds a user provided Stats struct to the parser to allow the user to process the results after the parsing has finished. Also the key for the "no match" counter is set.
Example usage:
input := "input"
stats := Stats{}
_, err := Parse("input-file", []byte(input), Statistics(&stats, "no match"))
if err != nil {
log.Panicln(err)
}
b, err := json.MarshalIndent(stats.ChoiceAltCnt, "", " ")
if err != nil {
log.Panicln(err)
}
fmt.Println(string(b))
type Query ¶
type Query struct {
Sorting []string // sorting the result of the query
Condition any // the condition or a Node
}
Query holding the parsed query
type Stats ¶
type Stats struct {
// ExprCnt counts the number of expressions processed during parsing
// This value is compared to the maximum number of expressions allowed
// (set by the MaxExpressions option).
ExprCnt uint64
// ChoiceAltCnt is used to count for each ordered choice expression,
// which alternative is used how may times.
// These numbers allow to optimize the order of the ordered choice expression
// to increase the performance of the parser
//
// The outer key of ChoiceAltCnt is composed of the name of the rule as well
// as the line and the column of the ordered choice.
// The inner key of ChoiceAltCnt is the number (one-based) of the matching alternative.
// For each alternative the number of matches are counted. If an ordered choice does not
// match, a special counter is incremented. The name of this counter is set with
// the parser option Statistics.
// For an alternative to be included in ChoiceAltCnt, it has to match at least once.
ChoiceAltCnt map[string]map[string]int
}
Stats stores some statistics, gathered during parsing
Source Files