René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"String.slice(str, 0, -1) raises FunctionClauseError","articleBody":"**This snippet of Elixir:**\r\n\r\n`String.slice(str, 0, -1)`\r\n\r\nStarted with slice/2 form of this call, but swapped to slice/3 to confirm the error wasn't being generated by the Elixir range.\r\n\r\n**Raises the following exception**\r\n\r\n\u003e ** (EXIT from #PID\u003c0.95.0\u003e) an exception was raised:\r\n\u003e     ** (FunctionClauseError) no function clause matching in ElixirScript.Translate.Form.compile/2\r\n\u003e         lib/elixir_script/passes/translate/form.ex:28: ElixirScript.Translate.Form.compile(\u0026Inspect.inspect/2, %{anonymous_fn: false, function: {:__struct__, nil}, in_guard: false, module: Inspect.Opts, pid: #PID\u003c0.200.0\u003e, vars: %{}})\r\n\u003e         lib/elixir_script/passes/translate/form.ex:16: ElixirScript.Translate.Form.compile!/2\r\n\u003e         lib/elixir_script/passes/translate/forms/map.ex:37: anonymous fn/2 in ElixirScript.Translate.Forms.Map.compile/2\r\n\u003e         (elixir 1.10.4) lib/enum.ex:1396: Enum.\"-map/2-lists^map/1-0-\"/2\r\n\u003e         (elixir 1.10.4) lib/enum.ex:1396: Enum.\"-map/2-lists^map/1-0-\"/2\r\n\u003e         lib/elixir_script/passes/translate/forms/map.ex:32: ElixirScript.Translate.Forms.Map.compile/2\r\n\u003e         lib/elixir_script/passes/translate/form.ex:16: ElixirScript.Translate.Form.compile!/2\r\n\u003e         lib/elixir_script/passes/translate/function.ex:170: ElixirScript.Translate.Function.compile_block/2\r\n\r\n**Modified Transcript.Form.compile! as follows:**\r\n\r\n```\r\n  @spec compile!(any, map) :: ESTree.Node.t()\r\n  def compile!(ast, state) do\r\n    {js_ast, _} = compile(ast, state)\r\n    js_ast\r\n  rescue\r\n    e -\u003e Logger.debug inspect({:compile!, ast, state})\r\n         raise RuntimeError, message: inspect({\"compile!/2\", e})\r\n  end\r\n```\r\n\r\n**Which revealed the following debugging info:**\r\n\r\n\u003e 03:45:21.580 [debug] {:compile!, \u0026Inspect.inspect/2, %{anonymous_fn: false, function: {:__struct__, nil}, in_guard: false, module: Inspect.Opts, pid: #PID\u003c0.200.0\u003e, vars: %{}}}\r\n\u003e \r\n\u003e 03:45:21.696 [debug] {:compile!, {:%{}, [line: 74], [__struct__: Inspect.Opts, base: :decimal, binaries: :infer, char_lists: :infer, charlists: :infer, custom_options: [], inspect_fun: \u0026Inspect.inspect/2, limit: 50, pretty: false, printable_limit: 4096, safe: true, structs: true, syntax_colors: [], width: 80]}, %{anonymous_fn: false, function: {:__struct__, nil}, in_guard: false, module: Inspect.Opts, pid: #PID\u003c0.200.0\u003e, vars: %{}}}\r\n\r\n**Thoughts**\r\n\r\nNot too familiar with this codebase, but I'm working from the premise that `inspect_fun: \u0026Inspect.inspect/2` might be malformed, for it to be promoted into the `ast` parameter of `compile!`.","author":{"url":"https://github.com/beadsland","@type":"Person","name":"beadsland"},"datePublished":"2020-08-01T08:40:06.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/496/elixirscript/issues/496"}