Revert #7964

Somehow the test case doesn't crash anymore and the regression in the
doc generation is fixed.

Fixes #9019

tests/let/t7936.nim

@@ -0,0 +1,27 @@
+discard """
+  action: "run"
+"""
+
+import
+  tables, deques, sequtils
+
+const
+  lookupTable = {'(': ')', '{': '}', '[': ']'}.toTable
+
+proc isPaired*(value: string): bool =
+  var stack = initDeque[char]() 
+
+  for item in value:
+    # echo "Looking at " & item
+    if item in lookupTable:
+      stack.addLast(item)
+    if item in toSeq(lookupTable.values):
+      if stack.len == 0:
+        return false
+      if lookupTable[stack.popLast()] != item:
+        return false
+
+  return stack.len == 0
+
+doAssert isPaired("{[()]}") == true
+doAssert isPaired("a)b(c") == false