Debugging

When your expression shows a red error banner, these techniques help you figure out what's going wrong.

Expression Code

// Debugging - Throw Error
// Use to debug values in expressions
throw new Error("Error is: " + value);

// Try-Catch Error Handling
// Wrap risky code to handle errors gracefully

try {
  var path = thisComp.layer("SEG-1").content("Path 1").path;
  var trimPath = thisComp.layer("SEG-1").content("Trim Paths 1").end / 100;
  var targetLayer = thisComp.layer("SEG-1");
  var point = path.pointOnPath(trimPath);

  targetLayer.toComp(point);
} catch (e) {
  // Fallback value if error occurs
  [0, 0];
}

Two techniques: **throw new Error()** — Intentionally trigger an error to see a variable's value. The error banner will show what you passed. Remove it once you've found the issue. **try/catch** — Wrap risky code so errors don't break your comp. If something fails, the catch block provides a fallback value instead of a red error.

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