Documentation
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Overview ¶
Package tag expands JaWS tag values into the comparable keys used to find elements during dirtying, broadcasts and event routing.
The runtime tag-comparability check in TagExpand is gated on deadlock.Debug, so it (and full statement coverage of this package) is only exercised when the tests run with the -race flag or -tags debug. Always test with -race.
Index ¶
- Variables
- func FindTagGetter(x any) (path string, tgType reflect.Type, found bool)
- func MustTagExpand(ctx Context, tag any) []any
- func NewErrNotComparable(x any) error
- func NewErrNotUsableAsTag(x any) error
- func TagExpand(ctx Context, tag any) ([]any, error)
- func TagString(tag any) string
- type Context
- type Tag
- type TagGetter
Constants ¶
This section is empty.
Variables ¶
var ErrIllegalTagType errIllegalTagType
ErrIllegalTagType is returned when a UI tag type is disallowed.
var ErrNotComparable errNotComparable
ErrNotComparable is returned when a UI object or tag is not comparable.
var ErrNotUsableAsTag errNotUsableAsTag
ErrNotUsableAsTag is returned when a value cannot be used as a tag.
It is also matchable as ErrNotComparable for backwards compatibility.
var ErrTooManyTags errTooManyTags
ErrTooManyTags is returned when tag expansion exceeds the recursion depth (maxTagDepth) or result count (maxTagCount) limits.
Functions ¶
func FindTagGetter ¶
FindTagGetter searches x recursively for a nested TagGetter.
The search is bounded: it follows at most maxTagDepth levels of nesting and scans only the first maxHintScan elements of any array or slice. It is used only to enrich the ErrNotUsableAsTag diagnostic, so these bounds trade completeness for a cheap, terminating search.
func MustTagExpand ¶
MustTagExpand calls TagExpand and either logs or panics if expansion fails.
When ctx is non-nil, expansion errors are passed to [Context.MustLog] and the partial result is returned. When ctx is nil, MustTagExpand panics.
func NewErrNotComparable ¶
NewErrNotComparable returns ErrNotComparable if x is not comparable.
func NewErrNotUsableAsTag ¶
NewErrNotUsableAsTag returns ErrNotUsableAsTag if x cannot be used as a tag.
func TagExpand ¶
TagExpand expands tag into a flat list of unique comparable tag values.
tag may be nil, a Tag, a slice of tags, a TagGetter or another comparable value. Primitive HTML/value types are rejected with ErrIllegalTagType to catch common accidental tags.
Types ¶
type Context ¶
type Context interface {
// Initial returns the Request's initial HTTP request, or nil.
Initial() (r *http.Request)
// Get returns the JaWS session value for the key, or nil.
Get(key string) any
// Set sets the JaWS session value for the key.
Set(key string, value any)
// Context returns the Request's context.
Context() (ctx context.Context)
// Log sends an error to the Logger set in the Jaws.
// Has no effect if the err is nil or the Logger is nil.
// Returns err.
Log(err error) error
// MustLog sends an error to the Logger set in the Jaws or
// panics with the given error if no Logger is set.
// Has no effect if the err is nil.
MustLog(err error)
}
Context is the request state made available while expanding tags.
Source Files