84 lines
1.9 KiB
Go
84 lines
1.9 KiB
Go
package via
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import (
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"fmt"
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"strconv"
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"strings"
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"github.com/ryanhamamura/via/h"
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)
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// Signal represents a value that is reactive in the browser. Signals
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// are synced with the server right before an action triggers.
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//
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// Use Bind() to connect a signal to an input and Text() to display it
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// reactively on an html element.
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type Signal struct {
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id string
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val any
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changed bool
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err error
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}
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// ID returns the signal ID.
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func (s *Signal) ID() string {
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return s.id
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}
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// Err returns a signal error or nil if it contains no error.
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//
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// It is useful to check for errors after updating signals with
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// dynamic values.
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func (s *Signal) Err() error {
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return s.err
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}
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// Bind binds this signal to an input element. When the input changes
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// its value the signal updates in real-time in the browser.
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//
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// Example:
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//
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// h.Input(h.Type("number"), mysignal.Bind())
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func (s *Signal) Bind() h.H {
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return h.Data("bind", s.id)
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}
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// Text binds the signal value to an html span element as text.
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//
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// Example:
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//
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// h.Div(mysignal.Text())
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func (s *Signal) Text() h.H {
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return h.Span(h.Data("text", "$"+s.id))
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}
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// SetValue updates the signal’s value and marks it for synchronization with the browser.
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// The change will be propagated to the browser using *Context.Sync() or *Context.SyncSignals().
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func (s *Signal) SetValue(v any) {
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s.val = v
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s.changed = true
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s.err = nil
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}
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// String returns the signal value as a string.
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func (s *Signal) String() string {
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return fmt.Sprintf("%v", s.val)
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}
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// Bool tries to read the signal value as a bool.
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// Returns the value or false on failure.
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func (s *Signal) Bool() bool {
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val := strings.ToLower(s.String())
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return val == "true" || val == "1" || val == "yes" || val == "on"
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}
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// Int tries to read the signal value as an int.
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// Returns the value or 0 on failure.
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func (s *Signal) Int() int {
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if n, err := strconv.Atoi(s.String()); err == nil {
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return n
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}
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return 0
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}
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