Added cache entry in tutorial. Improved docs.

README.md

@@ -11,9 +11,10 @@ it in a REPL (Read-Eval-Print-Loop) fashion, by inserting a "Compile" step in th
 of the loop -- so it's a Read-Compile-Run-Print-Loop -- while still feeling very interactive. 
 
 **GoNB** leverages that compilation speed to implement a full-featured (at least it's getting there)
-[Jupyter notebook](https://jupyter.org/) kernel.
+[Jupyter notebook](https://jupyter.org/) kernel. As a side benefit it works with packages that use CGO -- although it
+won't parse C code in the cells, so it can't be used as a C kernel.
 
-It already includes many goodies: contextual help and auto-complete (with 
+It already includes many goodies: cache between cell of results, contextual help and auto-complete (with 
 [`gopls`](https://github.com/golang/tools/tree/master/gopls)), compilation error context (by
 mousing over), bash command execution, images, html, etc. See the [tutorial](examples/tutorial.ipynb).
 
@@ -101,9 +102,6 @@ Contributions are welcome!
 * Windows version: 
   * Installation.
   * Named-pipe implementation in `kernel/pipeexec.go`.
-* Tracking of lines on generated Go files back to cell, so reported errors are easy to
-  follow. In the meantime the errors can be moused over and will display the lines
-  surrounding them.
 * Controllable (per package or file) logging in GoNB code. 
 * Run `goimports` before calling `gopls` to inspect a variable, or auto-complete. This
   would be handy, but complicates tracking the position of the cursor on the changed

docs/CHANGELOG.md

@@ -1,6 +1,6 @@
 # GoNB Changelog
 
-## Next version
+## v0.6.0
 
 * Issue #16: Added package `cache`: implements a convenient cache of values for things that
   are expensive or slow to regenerate at each execution.

examples/tutorial.ipynb

@@ -36,6 +36,7 @@
     }
    ],
    "source": [
+    "!*go mod edit --replace github.com/janpfeifer/gonb=/home/janpf/Projects/gonb\n",
     "func main() {\n",
     "    fmt.Printf(\"Hello World!\")\n",
     "}"
@@ -186,6 +187,61 @@
     "fmt.Printf(\"current startValue=%f\\n\", startValue)"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "f4fc0797-df7f-4652-8a22-e8b489580e1d",
+   "metadata": {},
+   "source": [
+    "If one wants to save results calculated from one cell to another, GoNB includes the `github.com/janpfeifer/gonb/cache` package that makes it trivial to save and load previously generated results.\n",
+    "\n",
+    "**Example**: Below `VeryExpensive` is only called once for `CachedValue`, so you will notice that if you run the cell multiple times, it will display always the same number, while `NonCachedValue` will always call `VeryExpensive` again, and display another number. So the string \"...calculating...\" is printed twice only the first time."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 27,
+   "id": "d59e0cbd-0d2a-42e5-8f94-29936130f437",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "\t...calculating...\n",
+      "NonCachedValue=575\n",
+      "   CachedValue=36\n"
+     ]
+    }
+   ],
+   "source": [
+    "import (\n",
+    "    \"math/rand\"\n",
+    "    \"github.com/janpfeifer/gonb/cache\"\n",
+    ")\n",
+    "\n",
+    "func VeryExpensive() int {\n",
+    "    fmt.Println(\"\\t...calculating...\")\n",
+    "    return rand.Intn(1000)\n",
+    "}\n",
+    "\n",
+    "var (\n",
+    "    CachedValue = cache.Cache(\"expensive\", VeryExpensive)\n",
+    "    NonCachedValue = VeryExpensive()\n",
+    ")\n",
+    "    \n",
+    "%%\n",
+    "fmt.Printf(\"NonCachedValue=%d\\n\", NonCachedValue)\n",
+    "fmt.Printf(\"   CachedValue=%d\\n\", CachedValue)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "5a5470b4-43ea-47ae-a111-63ab77376bd0",
+   "metadata": {},
+   "source": [
+    "The `cache` package has many more features, check out "
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "83c85334-6323-4b75-b9a2-184c0d83ed1c",
@@ -1325,7 +1381,7 @@
    "name": "go",
    "nbconvert_exporter": "",
    "pygments_lexer": "",
-   "version": "go1.20.1"
+   "version": "go1.20.3"
   }
  },
  "nbformat": 4,