Module response/code_editor

A code editor response element facilitates open-ended code-writing questions. Here's an example:

export const Practice_Question_List_Index_Of : QuestionSpecification = {
  question_id: "recursion_list_index_of",
  tags: [],
  points: 8,
  mk_description:
`For this question, you will work with a structure of nodes (see reference material) representing a **singly linked list** of integers.

Consider the \`index_of\` function below, which searches a **singly linked list** represented by \`Node\`s for a particular value and returns the 0-based index at which that value first occurs (or \`-1\` if the value is not found).

The \`index_of\` function internally calls a helper function \`index_of_helper\`, passing in an initial value of \`0\` for the \`index\` parameter:

\`\`\`cpp
// EFFECTS: Returns the index at which 'value' first occurs in the
//          given list. If the value does not occur, returns -1.
Node *index_of(Node *node, int value) {
    return index_of_helper(node, value, 0);
}
\`\`\`

Implement the \`index_of_helper\` function below.

- Your implementation should work correctly for any list.
- Your code **must** use recursion (and **may not** use any loops).
- Your implementation must be **tail recursive**.
- You may not call any functions, other than calling \`index_of_helper\` recursively.`,
  response: {
    kind: "code_editor",
    codemirror_mime_type: "text/x-c++src",
    code_language: "cpp",
    header: "int index_of_helper(Node *node, int value, int index) {",
    starter: "",
    footer: "}",
    sample_solution:
`if (!node) {
  return -1;
 }
 if (node->datum == value) {
  return index;
 }
 return index_of_helper(node->next, value, index + 1);`
  }
};

You'll want to specify the language you're working with in two places.

• code_language: For highlighting in the header/footer, specify the alias for any highlightjs supported language. For no highlighting, specify "text".

• codemirror_mime_type: For syntax highlighting and language support within the code editor itself, specify one of the MIME types supported by CodeMirror (click into the language you want, then scroll to the bottom to see the relevant MIME type). For no highlighting, specify "null".

The header and footer options specify code above/below the editor. Students can't edit the header/footer code. The starter options specifies code to initially populate the code editor, which students can change.

A submission for an code editor response is simply a string with whatever content was in the code editor box. See CodeEditorSubmission for details.