examples are not 100% type safe

[0xMALVEE]

Problem Examples are not 100% typesafe after I copy code I get a lot of type errors.

Solution Improve type safety

Alternatives No alternative

Context Typescript improvements of types in examples.

[dylans]

It is indeed difficult to keep the examples safe as every version of TS potentially introduces changes that were not caught previously.

PRs are always welcome to update them.

[alexander-larsson]

Sorry if this is not 100% related to this issue but I just started using Slate and got really confused by this when trying to get some code working based on the examples. Is it just the types that are wrong or does the type property for example in fact not exist on BaseElement (see one of the errors in the picture above) so the example code is wrong and based on some older version of Slate?

[maral]

Hi, I stumbled upon the very same thing and found a solution around the internet. However, it would be really nice if Slate's Docs already provided that - I really like everything about the design and philosophy of Slate, this was a turn off though. GitBook has the option to have multiple "tabs" in the docs to allow both JS and TS versions, see their examples.

Here is my take of correctly typed example from the 05-executing-commands walk through part:

'use client';

import React, { useCallback, useState } from 'react';
import type { BaseEditor, Descendant } from 'slate';
import { createEditor, Editor, Element, Transforms } from 'slate';
import type { ReactEditor, RenderElementProps, RenderLeafProps } from 'slate-react';
import { Editable, Slate, withReact } from 'slate-react';

type Paragraph = { type: 'paragraph'; children: CustomText[] };
type Code = { type: 'code'; children: CustomText[] };
type CustomElement = Paragraph | Code;
type CustomText = { text: string; bold: boolean };

declare module 'slate' {
  interface CustomTypes {
    Editor: BaseEditor & ReactEditor;
    Element: CustomElement;
    Text: CustomText;
  }
}

const initialValue: Descendant[] = [
  {
    type: 'paragraph',
    children: [{ text: 'A line of text in a paragraph.', bold: false }],
  },
];

const CustomEditor = {
  isBoldMarkActive(editor: Editor) {
    const marks = Editor.marks(editor);
    return marks ? marks.bold === true : false;
  },

  isCodeBlockActive(editor: Editor) {
    const [match] = Editor.nodes(editor, {
      match: n => Element.isElement(n) && n.type === 'code',
    });

    return !!match;
  },

  toggleBoldMark(editor: Editor) {
    const isActive = CustomEditor.isBoldMarkActive(editor);
    if (isActive) {
      Editor.removeMark(editor, 'bold');
    } else {
      Editor.addMark(editor, 'bold', true);
    }
  },

  toggleCodeBlock(editor: Editor) {
    const isActive = CustomEditor.isCodeBlockActive(editor);
    Transforms.setNodes(
      editor,
      { type: isActive ? undefined : 'code' },
      { match: n => Element.isElement(n) && Editor.isBlock(editor, n) }
    );
  },
};

export const EditorTest: React.FC = () => {
  const [editor] = useState(() => withReact(createEditor()));
  const renderElement = useCallback((props: RenderElementProps) => {
    switch (props.element.type) {
      case 'code':
        return <CodeElement {...props} />;
      default:
        return <DefaultElement {...props} />;
    }
  }, []);

  const renderLeaf = useCallback((props: RenderLeafProps) => {
    return <Leaf {...props} />;
  }, []);

  return (
    <div className='mx-auto max-w-2xl py-16 px-4 sm:py-24 sm:px-6 lg:max-w-7xl lg:px-8'>
      <Slate editor={editor} initialValue={initialValue}>
        <div className='flex mb-4 gap-2'>
          <button
            className='p-2 bg-blue-500 text-white rounded-md'
            onMouseDown={event => {
              event.preventDefault();
              CustomEditor.toggleBoldMark(editor);
            }}
          >
            Bold
          </button>
          <button
            className='p-2 bg-blue-500 text-white rounded-md'
            onMouseDown={event => {
              event.preventDefault();
              CustomEditor.toggleCodeBlock(editor);
            }}
          >
            Code Block
          </button>
        </div>
        <Editable
          renderElement={renderElement}
          renderLeaf={renderLeaf}
          onKeyDown={event => {
            if (!event.ctrlKey) {
              return;
            }

            switch (event.key) {
              case '`': {
                event.preventDefault();
                CustomEditor.toggleCodeBlock(editor);
                break;
              }

              case 'b': {
                event.preventDefault();
                CustomEditor.toggleBoldMark(editor);
                break;
              }
            }
          }}
        />
      </Slate>
    </div>
  );
};

const CodeElement = (props: RenderElementProps) => {
  return (
    <pre {...props.attributes}>
      <code>{props.children}</code>
    </pre>
  );
};

const DefaultElement = (props: RenderElementProps) => {
  return <p {...props.attributes}>{props.children}</p>;
};

const Leaf = (props: RenderLeafProps) => {
  return (
    <span
      {...props.attributes}
      style={{ fontWeight: props.leaf.bold ? 'bold' : 'normal', color: props.leaf.bold ? 'red' : 'black' }}
    >
      {props.children}
    </span>
  );
};

[KarsonJo]

In fact most type errors stem from not defining the editor types. This issue is actually addressed in the documentation. You can also get the type definition from inside the example. But it would be great if this information could be shown in the comments of the examples.