52 lines
1.3 KiB
Go
52 lines
1.3 KiB
Go
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package adapter
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// ConstraintValuer allows constraints to use specific values of their own.
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type ConstraintValuer interface {
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ConstraintValue() interface{}
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}
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// Constraint interface represents a single condition, like "a = 1". where `a`
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// is the key and `1` is the value. This is an exported interface but it's
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// rarely used directly, you may want to use the `db.Cond{}` map instead.
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type Constraint interface {
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// Key is the leftmost part of the constraint and usually contains a column
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// name.
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Key() interface{}
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// Value if the rightmost part of the constraint and usually contains a
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// column value.
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Value() interface{}
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}
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// Constraints interface represents an array of constraints, like "a = 1, b =
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// 2, c = 3".
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type Constraints interface {
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// Constraints returns an array of constraints.
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Constraints() []Constraint
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}
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type constraint struct {
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k interface{}
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v interface{}
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}
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func (c constraint) Key() interface{} {
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return c.k
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}
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func (c constraint) Value() interface{} {
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if constraintValuer, ok := c.v.(ConstraintValuer); ok {
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return constraintValuer.ConstraintValue()
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}
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return c.v
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}
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// NewConstraint creates a constraint.
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func NewConstraint(key interface{}, value interface{}) Constraint {
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return &constraint{k: key, v: value}
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}
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var (
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_ = Constraint(&constraint{})
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)
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