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HTML

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Insecure Resource

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <p>Demo of idea of how a CSS-like idea can be used for author intent. Idea is from <a href="https://codepen.io/bkardell/pen/xxLKOxo?editors=1111">Brian Kardell's codepen</a> with extended examples. The code uses CSS selectors and a custom property (<code>speech</code>) to generate text to use as the value of <code>aria-label</code>.</p>
<p>Note: these examples won't display well in Chrome/Edge as the examples depend upon some MathML features not yet implemented.
  This does not affect the computation of <code>aria-label</code></p>
Example 1:
<math>
  <mrow data-intent="point">
    <mo>(</mo>
    <mi class="arg1">0</mi>
    <mo>,</mo>
    <mi class="arg2">5</mi>
    <mo>)</mo>
  </mrow>
</math>
<br/>
Example 2:
<math>
<mover data-intent="line-segment">
  <mrow>
    <msup class="start" data-intent="modified-identifier">
      <mi class="base">A</mi>
      <mo class="modifier">&#x2032;</mo>
    </msup>
    <mo>&#x2063;</mo>
    <msup class="end" data-intent="modified-identifier">
      <mi class="base">B</mi>
      <mo class="modifier">&#x2032;</mo>
    </msup>
  </mrow>
  <mo>¯</mo>
</mover>
</math>
<br/>
Example 3:
<math>
  <msub data-intent="point-coordinate">
    <msup class="point" data-intent="modified-identifier">
      <mi class="base">B</mi>
      <mo class="modifier">&#x2032;</mo>
    </msup>
    <mi class="coord">x<mi>
  </msub>
</math>
!

CSS 

              
                [data-intent="point"] {
   --speech: "the point " text(.arg1) " comma " text(.arg2);
}

[data-intent="line-segment"] {
   --speech: "the line segment " text(.start) "  " text(.end);
}

[data-intent="modified-identifier"] {
   --speech: text(.base) " " text(.modifier);
}

[data-intent="point-coordinate"] {
   --speech: "the " text(.coord) "coordinate of " text(.point);
}
!

JS 

              
                function parseIntentExpression(str, context) {
  const regex = /\W[^\"]*/gm;
  let m,  mode = '', out = ''
  //console.warn("parse: intent/str=" + str + ", el/context=" + context.outerHTML)
  while ((m = regex.exec(str)) !== null) {
      // avoid infinite loops with zero-width matches
      if (m.index === regex.lastIndex) {
          regex.lastIndex++;
      }
      m.forEach((match, groupIndex) => {
        let tok = match.substring(1)
         if ((mode === '')  && match[0]==='"') {
          mode = "string"
          out += tok
         } else if (tok !== "" ) {
           tok = tok.trim()
           if (tok.startsWith('text(')) {
             tok = tok.substring(5, tok.length-1)
             console.warn("querying '" + tok + "'")
             let el = context.querySelector(tok)
             console.warn("outerHTML:" + el.outerHTML)
             console.warn("textContent:" + el.textContent)
             if(el) {
               out += el.textContent
             } else {
               console.warn('no element matching ', tok)
             }
           } else {
             console.warn(`unsupported token ${tok} in expression ${str}`)
           }
           mode = "" //reset
         }
      });
  }
  return out
}

// a 'static' profile, could be improved with a defined lifecycle for recalc
document.addEventListener("DOMContentLoaded", ()=> {
  let intents = document.querySelectorAll('[data-intent]')
  intents.forEach(intentEl => {
    let intentExpression = getComputedStyle(intentEl).getPropertyValue('--speech')
    let value = parseIntentExpression(intentExpression, intentEl)
    
    // somehow, attach the meaning
    intentEl.setAttribute('aria-label', value)
  })
})
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999px

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