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expr

package

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Versions in this module

v0

v0.10.0

Feb 2, 2026

Changes in this version

type Evaluator

+ func BindEvaluator2[T, U any, E Evaluator](eval func(T, U) E, t bind.Binder[T], u bind.Binder[U]) Evaluator

+ func BindEvaluator3[T, U, V any, E Evaluator](eval func(T, U, V) E, t bind.Binder[T], u bind.Binder[U], v bind.Binder[V]) Evaluator

+ func BindEvaluator[T any, E Evaluator](factory func(T) E, t bind.Binder[T]) Evaluator

v0.9.4

Dec 23, 2025

v0.9.3

Nov 17, 2025

v0.9.2

Jul 15, 2025

Changes in this version

+ const AlwaysFalse

+ const AlwaysTrue

+ func AddExpr(e *Expr) cli.Action

+ func AddExprs(exprs ...*Expr) cli.Action

+ func SetEvaluator(e Evaluator) cli.Action

+ type Binding interface

+ Expr func() *Expr

+ func NewBinding(ev Evaluator, exprlookup ...any) Binding

+ type Evaluator interface

+ Evaluate func(c context.Context, v any, yield func(any) error) error

+ func ComposeEvaluator(e ...Evaluator) Evaluator

+ func Error(err error) Evaluator

+ func EvaluatorOf(v any) Evaluator

+ type EvaluatorFunc func(*cli.Context, any, func(any) error) error

+ func (e EvaluatorFunc) Evaluate(c context.Context, v any, yield func(any) error) error

+ type Expr struct

+ After any

+ Aliases []string

+ Args []*cli.Arg

+ Before any

+ Category string

+ Data map[string]any

+ Description any

+ Evaluate any

+ HelpText string

+ ManualText string

+ Name string

+ Options cli.Option

+ UsageText string

+ Uses any

+ func (e *Expr) Arg(name any) (*cli.Arg, bool)

+ func (e *Expr) LocalArgs() []*cli.Arg

+ func (e *Expr) LookupData(name string) (any, bool)

+ func (e *Expr) Names() []string

+ func (e *Expr) SetAliases(a []string)

+ func (e *Expr) SetCategory(name string)

+ func (e *Expr) SetData(name string, v any)

+ func (e *Expr) SetDescription(value string)

+ func (e *Expr) SetHelpText(name string)

+ func (e *Expr) SetHidden(value bool)

+ func (e *Expr) SetLocalArgs(args []*cli.Arg) error

+ func (e *Expr) SetManualText(name string)

+ func (e *Expr) SetName(name string)

+ func (e *Expr) SetUsageText(value string)

+ func (e *Expr) Synopsis() string

+ type Expression struct

+ Exprs []*Expr

+ func FromContext(c *cli.Context, name string) *Expression

+ func (e *Expression) Append(expr Binding)

+ func (e *Expression) Bindings() iter.Seq[Binding]

+ func (e *Expression) Evaluate(ctx context.Context, items ...any) error

+ func (e *Expression) Initializer() cli.Action

+ func (e *Expression) Prepend(expr Binding)

+ func (e *Expression) Set(arg string) error

+ func (e *Expression) String() string

+ func (e *Expression) VisibleExprs() []*Expr

+ func (e *Expression) Walk(fn func(Binding) error) error

+ type Invariant bool

+ func (i Invariant) Evaluate(_ context.Context, v any, y func(any) error) error

+ type Predicate func(v any) bool

+ func (p Predicate) Evaluate(c context.Context, v any, yield func(any) error) error

+ type Yielder func(any) error

v0.9.1

Apr 15, 2025

v0.9.0

Mar 18, 2025