excellent

Documentation

Index

• func EvaluateExpression(env utils.Environment, context types.XValue, expression string) types.XValue
• func EvaluateTemplate(env utils.Environment, context types.XValue, template string, ...) (string, error)
• func EvaluateTemplateValue(env utils.Environment, context types.XValue, template string, ...) (types.XValue, error)
• func VisitExpression(expression string, visitor antlr.ParseTreeVisitor) (interface{}, error)
• func VisitTemplate(template string, allowedTopLevels []string, ...) error
• type ErrorListener
  • func NewErrorListener(expression string) *ErrorListener
  • func (l *ErrorListener) Errors() []error
  • func (l *ErrorListener) SyntaxError(recognizer antlr.Recognizer, offendingSymbol interface{}, line, column int, ...)
• type Scanner
  • func NewXScanner(r io.Reader, identifierTopLevels []string) Scanner
• type TemplateError
  • func (e TemplateError) Error() string
• type TemplateErrors
  • func NewTemplateErrors() *TemplateErrors
  • func (e *TemplateErrors) Add(expression, message string)
  • func (e *TemplateErrors) Error() string
  • func (e *TemplateErrors) HasErrors() bool
• type XTokenType

Functions

func EvaluateExpression

func EvaluateExpression(env utils.Environment, context types.XValue, expression string) types.XValue

EvaluateExpression evalutes the passed in Excellent expression, returning the typed value it evaluates to, which might be an error, e.g. "2 / 3" or "contact.fields.age"

func EvaluateTemplate

func EvaluateTemplate(env utils.Environment, context types.XValue, template string, allowedTopLevels []string) (string, error)

EvaluateTemplate evaluates the passed in template

func EvaluateTemplateValue

func EvaluateTemplateValue(env utils.Environment, context types.XValue, template string, allowedTopLevels []string) (types.XValue, error)

EvaluateTemplateValue is equivalent to EvaluateTemplate except in the case where the template contains a single identifier or expression, ie: "@contact" or "@(first(contact.urns))". In these cases we return the typed value from EvaluateExpression instead of stringifying the result.

func VisitExpression

func VisitExpression(expression string, visitor antlr.ParseTreeVisitor) (interface{}, error)

VisitExpression parses and visits the given expression with the given visitor

func VisitTemplate

func VisitTemplate(template string, allowedTopLevels []string, callback func(XTokenType, string) error) error

VisitTemplate scans the given template and calls the callback for each token encountered

Types

type ErrorListener

type ErrorListener struct {
	*antlr.DefaultErrorListener
	// contains filtered or unexported fields
}

ErrorListener records syntax errors

func NewErrorListener

func NewErrorListener(expression string) *ErrorListener

NewErrorListener creates a new error listener

func (*ErrorListener) Errors

func (l *ErrorListener) Errors() []error

Errors returns the errors encountered so far

func (*ErrorListener) SyntaxError

func (l *ErrorListener) SyntaxError(recognizer antlr.Recognizer, offendingSymbol interface{}, line, column int, msg string, e antlr.RecognitionException)

SyntaxError handles a new syntax error encountered by the recognizer

type Scanner

type Scanner interface {
	Scan() (XTokenType, string)
	SetUnescapeBody(bool)
}

Scanner is something which can scan tokens from input

func NewXScanner

func NewXScanner(r io.Reader, identifierTopLevels []string) Scanner

NewXScanner returns a new instance of our excellent scanner

type TemplateError

type TemplateError struct {
	// contains filtered or unexported fields
}

TemplateError is an error which occurs during evaluation of an expression

func (TemplateError) Error

func (e TemplateError) Error() string

type TemplateErrors

type TemplateErrors struct {
	// contains filtered or unexported fields
}

TemplateErrors represents the list of all errors encountered during evaluation of a template

func NewTemplateErrors

func NewTemplateErrors() *TemplateErrors

func (*TemplateErrors) Add

func (e *TemplateErrors) Add(expression, message string)

func (*TemplateErrors) Error

func (e *TemplateErrors) Error() string

Error returns a single string describing all the errors encountered

func (*TemplateErrors) HasErrors

func (e *TemplateErrors) HasErrors() bool

type XTokenType

type XTokenType int

XTokenType is a set of types than can be scanned

const (
	// BODY - Not in expression
	BODY XTokenType = iota

	// IDENTIFIER - 'contact.age' in '@contact.age'
	IDENTIFIER

	// EXPRESSION - the body of an expression '1+2' in '@(1+2)'
	EXPRESSION

	// EOF - end of expression
	EOF
)