63 lines
1.4 KiB
Go
63 lines
1.4 KiB
Go
package objects
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import "github.com/d5/tengo/compiler/token"
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// Undefined represents an undefined value.
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type Undefined struct{}
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// TypeName returns the name of the type.
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func (o *Undefined) TypeName() string {
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return "undefined"
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}
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func (o *Undefined) String() string {
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return "<undefined>"
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}
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// BinaryOp returns another object that is the result of
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// a given binary operator and a right-hand side object.
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func (o *Undefined) BinaryOp(op token.Token, rhs Object) (Object, error) {
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return nil, ErrInvalidOperator
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}
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// Copy returns a copy of the type.
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func (o *Undefined) Copy() Object {
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return o
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}
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// IsFalsy returns true if the value of the type is falsy.
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func (o *Undefined) IsFalsy() bool {
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return true
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}
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// Equals returns true if the value of the type
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// is equal to the value of another object.
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func (o *Undefined) Equals(x Object) bool {
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return o == x
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}
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// IndexGet returns an element at a given index.
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func (o *Undefined) IndexGet(index Object) (Object, error) {
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return UndefinedValue, nil
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}
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// Iterate creates a map iterator.
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func (o *Undefined) Iterate() Iterator {
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return o
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}
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// Next returns true if there are more elements to iterate.
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func (o *Undefined) Next() bool {
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return false
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}
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// Key returns the key or index value of the current element.
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func (o *Undefined) Key() Object {
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return o
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}
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// Value returns the value of the current element.
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func (o *Undefined) Value() Object {
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return o
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}
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