const regex = /^Q: ((?:.*|\n)*?)\n*A: (.+(?:\n(?:^.{1,3}$|^.{4}(?<!<!--).*))*)
/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('^Q: ((?:.*|\\n)*?)\\n*A: (.+(?:\\n(?:^.{1,3}$|^.{4}(?<!<!--).*))*)
', 'gm')
const str = `Q: diff between null and undefined?
A: Null indicates an intentional empty value.
- Undefined indicates the total absence of a value. This happen when only the variable was declared without any initializer. A missing key in an object is also undefined.
\`\`\`javascript
export function ticketStatus(tickets, ticketId) {
if (tickets[ticketId] === undefined) {
return 'unknown ticket id';
} else if (tickets[ticketId] === null) {
return 'not sold';
} else {
return \`sold to \${tickets[ticketId]}\`;
}
}
\`\`\`
<!--ID: 1673953179724-->
---
Q: rewrite to use [[JS Object.assign]]
\`\`\`javascript
visitor.ticketId = null;
return visitor;
\`\`\`
A: Just pass only the props we want to overwrite to assign
\`\`\`javascript
return Object.assign(visitor, {ticketId: null});
\`\`\`
<!--ID: 1673953179746-->
---
Q: diff between isNaN() global vs Number.isNaN()?
A: global isNaN() does type conversion.
- Since I am trying to test whether the string contains a valid number, this is the right choice.
- If the input is already a number, then Number.isNaN() might be better. as
---
`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions