Documentation
¶
Overview ¶
Package visitorgen is responsible for taking the ast.go of Vitess and and producing visitor infrastructure for it.
This is accomplished in a few steps. Step 1: Walk the AST and collect the interesting information into a format that is
easy to consume for the next step. The output format is a *SourceFile, that contains the needed information in a format that is pretty close to the golang ast, but simplified
Step 2: A SourceFile is packaged into a SourceInformation. SourceInformation is still
concerned with the input ast - it's just an even more distilled and easy to consume format for the last step. This step is performed by the code in transformer.go.
Step 3: Using the SourceInformation, the struct_producer.go code produces the final data structure
used, a VisitorPlan. This is focused on the output - it contains a list of all fields or arrays that need to be handled by the visitor produced.
Step 4: The VisitorPlan is lastly turned into a string that is written as the output of
this whole process.
Index ¶
- func EmitReplacementMethods(vd *VisitorPlan) string
- func EmitTypeSwitches(vd *VisitorPlan) string
- type Array
- type ArrayFieldItem
- type ArrayItem
- type Field
- type FuncDeclaration
- type InterfaceDeclaration
- type Ref
- type Sast
- type SingleFieldItem
- type SourceFile
- type SourceInformation
- type StructDeclaration
- type SwitchCase
- type Type
- type TypeAlias
- type TypeString
- type VisitorItem
- type VisitorPlan
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func EmitReplacementMethods ¶
func EmitReplacementMethods(vd *VisitorPlan) string
EmitReplacementMethods is an anti-parser (a.k.a prettifier) - it takes a struct that is much like an AST, and produces a string from it. This method will produce the replacement methods that make it possible to replace objects in fields or in slices.
func EmitTypeSwitches ¶
func EmitTypeSwitches(vd *VisitorPlan) string
EmitTypeSwitches is an anti-parser (a.k.a prettifier) - it takes a struct that is much like an AST, and produces a string from it. This method will produce the switch cases needed to cover the Vitess AST.
Types ¶
type Array ¶
type Array struct {
// contains filtered or unexported fields
}
Array is an array of things, such as `[]string`
type ArrayFieldItem ¶
ArrayFieldItem is an array field in a struct
type ArrayItem ¶
type ArrayItem struct {
StructType, ItemType Type
}
ArrayItem is an array that implements SQLNode
type Field ¶
type Field struct {
// contains filtered or unexported fields
}
Field is a field in a struct - a name with a type tuple
type FuncDeclaration ¶
type FuncDeclaration struct {
// contains filtered or unexported fields
}
FuncDeclaration represents a function declaration. These are tracked to know which types implement interfaces.
type InterfaceDeclaration ¶
type InterfaceDeclaration struct {
// contains filtered or unexported fields
}
InterfaceDeclaration represents a declaration of an interface. This is used to keep track of which types need to be handled by the visitor framework
type Ref ¶
type Ref struct {
// contains filtered or unexported fields
}
Ref is a reference to something, such as `*string`
type Sast ¶
type Sast interface {
// contains filtered or unexported methods
}
Sast or simplified AST, is a representation of the ast.go lines we are interested in
type SingleFieldItem ¶
SingleFieldItem is a single field in a struct
type SourceFile ¶
type SourceFile struct {
// contains filtered or unexported fields
}
SourceFile contains all important lines from an ast.go file
func Walk ¶
func Walk(node ast.Node) *SourceFile
Walk walks the given AST and translates it to the simplified AST used by the next steps
func (*SourceFile) String ¶
func (t *SourceFile) String() string
String returns a textual representation of the SourceFile. This is for testing purposed
type SourceInformation ¶
type SourceInformation struct {
// contains filtered or unexported fields
}
SourceInformation contains the information from the ast.go file, but in a format that is easier to consume
func Transform ¶
func Transform(input *SourceFile) *SourceInformation
Transform takes an input file and collects the information into an easier to consume format
func (*SourceInformation) String ¶
func (v *SourceInformation) String() string
type StructDeclaration ¶
type StructDeclaration struct {
// contains filtered or unexported fields
}
StructDeclaration represents a struct. It contains the fields and their types
type SwitchCase ¶
type SwitchCase struct {
Type Type
Fields []VisitorItem
}
SwitchCase is what we need to know to produce all the type switch cases in the visitor.
func (*SwitchCase) Len ¶
func (s *SwitchCase) Len() int
func (*SwitchCase) Less ¶
func (s *SwitchCase) Less(i, j int) bool
func (*SwitchCase) Swap ¶
func (s *SwitchCase) Swap(i, j int)
type Type ¶
type Type interface {
// contains filtered or unexported methods
}
Type represents a type in the golang type system. Used to keep track of type we need to handle, and the types of fields.
type TypeAlias ¶
type TypeAlias struct {
// contains filtered or unexported fields
}
TypeAlias is used whenever we see a `type XXX YYY` - XXX is the new name for YYY. Note that YYY could be an array or a reference
type TypeString ¶
type TypeString struct {
// contains filtered or unexported fields
}
TypeString is a raw type name, such as `string`
type VisitorItem ¶
type VisitorItem interface {
// contains filtered or unexported methods
}
VisitorItem represents something that needs to be added to the rewriter infrastructure
type VisitorPlan ¶
type VisitorPlan struct {
Switches []*SwitchCase // The cases for the big switch statement used to implement the visitor
}
VisitorPlan represents all the output needed for the rewriter
func ToVisitorPlan ¶
func ToVisitorPlan(input *SourceInformation) *VisitorPlan
ToVisitorPlan transforms the source information into a plan for the visitor code that needs to be produced
func (*VisitorPlan) Len ¶
func (v *VisitorPlan) Len() int
func (*VisitorPlan) Less ¶
func (v *VisitorPlan) Less(i, j int) bool
func (*VisitorPlan) String ¶
func (v *VisitorPlan) String() string
String returns a string, used for testing
func (*VisitorPlan) Swap ¶
func (v *VisitorPlan) Swap(i, j int)
Source Files
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Directories
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| Path | Synopsis |
|---|---|
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Package exit provides an alternative to os.Exit(int).
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Package exit provides an alternative to os.Exit(int). |
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Package tb exposes some handy traceback functionality buried in the runtime.
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Package tb exposes some handy traceback functionality buried in the runtime. |