mdast-range

mdast-range

Patch index-based ranges on mdast nodes, so you can slice sources!

Installation

npm

npm install mdast-range

Component.js

component install wooorm/mdast-range

Bower

bower install mdast-range

Duo

var range = require('wooorm/mdast-range');

UMD: globals, AMD, and CommonJS (uncompressed and compressed):

<script src="path/to/mdast.js"></script>
<script src="path/to/mdast-range.js"></script>
<script>
  mdast.use(mdastRange);
</script>

Table of Contents

• Usage

• API

  • mdast.use(range)

• License

Usage

Dependencies and input:

var range = require('mdast-range');
var mdast = require('mdast').use(range);
var doc = 'Some *emphasis*,\n**strongness**,\nand `code`.';

And when the plugin is run, the ast looks as follows:

mdast.process(doc);

Note the offset properties.

{
  "type": "root",
  "children": [
    {
      "type": "paragraph",
      "children": [
        {
          "type": "text",
          "value": "Some ",
          "position": {
            "start": {
              "line": 1,
              "column": 1,
              "offset": 0
            },
            "end": {
              "line": 1,
              "column": 6,
              "offset": 5
            },
            "indent": []
          }
        },
        {
          "type": "emphasis",
          "children": [
            {
              "type": "text",
              "value": "emphasis",
              "position": {
                "start": {
                  "line": 1,
                  "column": 7,
                  "offset": 6
                },
                "end": {
                  "line": 1,
                  "column": 15,
                  "offset": 14
                },
                "indent": []
              }
            }
          ],
          "position": {
            "start": {
              "line": 1,
              "column": 6,
              "offset": 5
            },
            "end": {
              "line": 1,
              "column": 16,
              "offset": 15
            },
            "indent": []
          }
        },
        {
          "type": "text",
          "value": ",\n",
          "position": {
            "start": {
              "line": 1,
              "column": 16,
              "offset": 15
            },
            "end": {
              "line": 2,
              "column": 1,
              "offset": 17
            },
            "indent": [
              1
            ]
          }
        },
        {
          "type": "strong",
          "children": [
            {
              "type": "text",
              "value": "strongness",
              "position": {
                "start": {
                  "line": 2,
                  "column": 3,
                  "offset": 19
                },
                "end": {
                  "line": 2,
                  "column": 13,
                  "offset": 29
                },
                "indent": []
              }
            }
          ],
          "position": {
            "start": {
              "line": 2,
              "column": 1,
              "offset": 17
            },
            "end": {
              "line": 2,
              "column": 15,
              "offset": 31
            },
            "indent": []
          }
        },
        {
          "type": "text",
          "value": ",\nand ",
          "position": {
            "start": {
              "line": 2,
              "column": 15,
              "offset": 31
            },
            "end": {
              "line": 3,
              "column": 5,
              "offset": 37
            },
            "indent": [
              1
            ]
          }
        },
        {
          "type": "inlineCode",
          "value": "code",
          "position": {
            "start": {
              "line": 3,
              "column": 5,
              "offset": 37
            },
            "end": {
              "line": 3,
              "column": 11,
              "offset": 43
            },
            "indent": []
          }
        },
        {
          "type": "text",
          "value": ".",
          "position": {
            "start": {
              "line": 3,
              "column": 11,
              "offset": 43
            },
            "end": {
              "line": 3,
              "column": 12,
              "offset": 44
            },
            "indent": []
          }
        }
      ],
      "position": {
        "start": {
          "line": 1,
          "column": 1,
          "offset": 0
        },
        "end": {
          "line": 3,
          "column": 12,
          "offset": 44
        },
        "indent": [
          1,
          1
        ]
      }
    }
  ],
  "position": {
    "start": {
      "line": 1,
      "column": 1,
      "offset": 0
    },
    "end": {
      "line": 3,
      "column": 12,
      "offset": 44
    }
  }
}

API

mdast.use(range)

Adds offset to each node’s Position.

Where normally nodes have a line based positional information, such as:

{
  "type": "break",
  "position": {
    "start": {
      "line": 2,
      "column": 5
    },
    "end": {
      "line": 3,
      "column": 1
    }
  }
}

...this plugin adds absolute positional information:

{
  "type": "break",
  "position": {
    "start": {
      "line": 2,
      "column": 5,
      "offset": 25
    },
    "end": {
      "line": 3,
      "column": 1,
      "offset": 26
    }
  }
}

...so you can slice (or syntax highlight) the source:

var line = doc.slice(node.position.start.offset, node.position.end.offset);
// Yields: `"\n"`

To reverse an offset into a position, pass it into file.offsetToPosition():

mdast.use(range).process('foo', function (err, doc, file) {
    file.offsetToPosition(0);
    // Yields: `{line: 1, column: 1}`
});

To turn any position object, use file.positionToOffset():

mdast.use(range).process('foo', function (err, doc, file) {
    var pos = file.offsetToPosition(0);

    file.positionToOffset(pos);
    // Yields: `0`.
});

License

MIT © Titus Wormer