planning

node_modules/micromark/lib/util/combine-extensions.mjs

@@ -0,0 +1,48 @@
+export default combineExtensions
+
+import own from '../constant/has-own-property.mjs'
+import chunkedSplice from './chunked-splice.mjs'
+import miniflat from './miniflat.mjs'
+
+// Combine several syntax extensions into one.
+function combineExtensions(extensions) {
+  var all = {}
+  var index = -1
+
+  while (++index < extensions.length) {
+    extension(all, extensions[index])
+  }
+
+  return all
+}
+
+function extension(all, extension) {
+  var hook
+  var left
+  var right
+  var code
+
+  for (hook in extension) {
+    left = own.call(all, hook) ? all[hook] : (all[hook] = {})
+    right = extension[hook]
+
+    for (code in right) {
+      left[code] = constructs(
+        miniflat(right[code]),
+        own.call(left, code) ? left[code] : []
+      )
+    }
+  }
+}
+
+function constructs(list, existing) {
+  var index = -1
+  var before = []
+
+  while (++index < list.length) {
+    ;(list[index].add === 'after' ? existing : before).push(list[index])
+  }
+
+  chunkedSplice(existing, 0, 0, before)
+  return existing
+}