✨ Deliberately fail an XMD document with `<Fail>` #659

Story

As an Executable Markdown author, I want to select an actionable failure in authored control flow, so abort and bounded exhaustion do not depend on a generic missing-<Return> diagnostic or a host-only branch.

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Issue #260 moves generation, repair, human review, abort, and bounded exhaustion into a checked-in Markdown value root. The root needs to fail deliberately on abort or when its review bound is exhausted. Falling through without <Return> reports a structural accident rather than the decision the document made.

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all \u003cpre\u003e\u003ccode\u003e blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks"); } } catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); } })(); (function(){ try { var __m = "github.com"; var __re = new RegExp('^' + "github\\.com" + '

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened

Story

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix"); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened

Story

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length \u003e 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened

Story

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

to join this conversation on GitHub. Already have an account? Sign in to comment

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Development

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened

Story

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

to join this conversation on GitHub. Already have an account? Sign in to comment

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Development

No branches or pull requests

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened

Story

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

to join this conversation on GitHub. Already have an account? Sign in to comment

Metadata

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Projects

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Development

No branches or pull requests

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened

Story

<Failmessage="Review aborted; nothing was saved or run." />

Contract

<Fail> is a generic first-party component.

It is self-closing and requires a non-empty string message.
It renders nothing, binds nothing, and declares no return value.
When expanded, it raises an authored failure carrying that message at the invocation position.
It performs no durable effect before failing.
It follows the enclosing error-mode contract. In a value root, the existing throw mode makes it fail the document even if a <PrintErrors> appears outside that value body.
Content, as, a missing message, and an empty message are refused before the failure body runs.

Suggested syntax description:

Stop authored work with an actionable failure. <Fail message="No acceptable candidate was approved." /> raises the message where it is written.

Motivation

Acceptance

A plain root reaches the authored failure and does not expand a following sibling.
A value root publishes no value and fails with the authored message.
A branch not taken reaches no failure.
A loop may select the failure on exhaustion.
Invalid invocation shape runs no authored failure body.
Error-mode behavior follows the existing specification, including an explicitly recovering <PrintErrors> region where applicable.
The component is documented in the syntax catalog and covered under Deno, Node and Bun through the shared corpus.

Relationship

This is a prerequisite for #260. It is generic control flow and contains no prompt-specific abort or retry policy.

to join this conversation on GitHub. Already have an account? Sign in to comment

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Projects

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Development

No branches or pull requests

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();

✨ Deliberately fail an XMD document with `<Fail>` #659

Closed

opened