Factor data-to-JSON-string construction out of stitches.

This is a recurring and nameable operation; let's give it a name before we use it further.

1 files changed, 1 insertions, 5 deletions

diff --git a/ui/lib/swatch/derive.js b/ui/lib/swatch/derive.js
index 85547e8..22ceb13 100644
--- a/ui/lib/swatch/derive.js
+++ b/ui/lib/swatch/derive.js
@@ -5,16 +5,12 @@ function tryDerive(args, func, fallback) {
   try {
     return func(...args);
   } catch (e) {
-    console.debug('deriver threw exception', e, func, args);
     return fallback;
   }
 }
 
 // A "deriver" is a function that never raises; if the underlying function would raise, the
 // corresponding deriver instead returns a fallback value (or `undefined`).
-export function makeDeriver(func, fallback) {
+export function makeDeriver(func, fallback = undefined) {
   return (...args) => tryDerive(args, func, fallback);
 }
-
-// Some widely-used derivers, for convenience.
-export const json = makeDeriver(JSON.parse);