Runtime helpers

These are the github.com/gsxhq/gsx types and functions commonly called from application code. See Attributes, Styling, and Escaping for their syntax and safety rules.

Core

Name	Declaration	Use
Node	type Node interface { Render(ctx context.Context, w io.Writer) error }	Renderable value returned by every component.
Func	type Func func(ctx context.Context, w io.Writer) error	Adapt a render function to Node; its Render method calls the function.

Trusted values

Name	Declaration	Use
Raw	func Raw(html string) Node	Render trusted HTML verbatim.
RawURL	type RawURL string	Trust a URL scheme while retaining attribute escaping.
RawJS	type RawJS string	Trust JavaScript and bypass JavaScript encoding.
RawCSS	type RawCSS string	Trust CSS and bypass CSS value filtering.

Each entry crosses a trust boundary. Pass only content you control or have validated for that context; see Escaping.

Node values

Name	Signature	Use
Val	func Val(v any) Node	Box a supported Go value as a Node.
Text	func Text(s string) Node	Create an HTML-escaped text node.
Fragment	func Fragment(nodes ...Node) Node	Render several nodes in order without a wrapper element.

Val accepts nil, Node, []Node, string, []byte, fmt.Stringer, bool, int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, float32, and float64. Other values return an error from Render. A named scalar without a supported interface must be converted to its built-in type before boxing it.

Attribute bags

Bag types

Name	Declaration or signature	Use
Attr	type Attr struct { Key string; Value any }	One ordered attribute pair.
Attrs	type Attrs []Attr	Ordered attribute bag.
AttrMap.ToAttrs	func (m AttrMap) ToAttrs() Attrs	Convert a map, sorted by key.

Attrs methods

Read values

Name	Signature	Use
Class	func (a Attrs) Class() string	Join class values.
Style	func (a Attrs) Style() string	Join style values.
Get	func (a Attrs) Get(key string) (any, bool)	Get the last value.
Has	func (a Attrs) Has(key string) bool	Did the caller supply the key? Present even when its value is false.
Bool	func (a Attrs) Bool(key string) bool	Boolean state of a key, as the spread renders it: Toggle/bool decide, nil or absent is false, anything else is true.

Presence vs state. disabled={expr} is in the bag whatever expr is; the false pair must stay so a later spread can override an earlier true, and so a component can tell "caller said false" from "caller said nothing". Has answers the second question and is the right guard for defaults: { if !attrs.Has("type") { type="button" } } lets a caller override with any value, including false. Bool answers "is it on?" for styling by state: disabled={false} is false, and so is aria-pressed={false} even though that one renders as aria-pressed="false" (see Boolean attributes). Get returns the raw value when you need to see the distinction yourself.

Keys are HTML attribute names and every accessor matches them as the browser does, ignoring ASCII case: Has("href") sees an HREF key. Get("style") returns the style already CSS-filtered, as gsx.RawCSS, so it can go back into a bag.

Transform bags

Name	Signature	Use
Without	func (a Attrs) Without(keys ...string) Attrs	Copy without keys.
Take	func (a Attrs) Take(key string) (any, Attrs)	Get and remove a key.
Merge	func (a Attrs) Merge(other Attrs) Attrs	Merge bags; class and style compose.

See Attributes for spread order and Styling for class and style precedence.