HTML Class Token Duplicate Audit

Audit class token duplicates using HTML ASCII whitespace splitting and exact case-sensitive token identity; does not parse selectors or CSS escapes.

Description

Audit class token duplicates using HTML ASCII whitespace splitting and exact case-sensitive token identity; does not parse selectors or CSS escapes.

A class attribute may repeat the same token. Grouping duplicate positions helps inspect how a generated class string was assembled.

When to use this tool

Audit class token duplicates using HTML ASCII whitespace splitting and exact case-sensitive token identity; does not parse selectors or CSS escapes.

Prepare the supplied classes fields for this operation.
Compare the complete example with the representation used by your own input before carrying the result into another step.

How to use the tool and how it works

Enter classes. Use the exact text syntax, units and index conventions explained below.
Run the tool. If input validation fails, correct the supplied fields before interpreting any result.
Read result.tokens, result.duplicates. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.

Tokenize classes on HTML ASCII whitespace. Return the full token sequence and groups whose exact token occurs more than once, with zero-based token indexes.^[1]

Input field	Meaning and representation	Accepted input
classes	classes.	Text; at most 8,192 UTF-16 code units, subject to the grammar above

Output field	Interpretation
result	Object containing the named outputs below.
result.tokens	The tokens list in the ordering and representation described above.
result.duplicates	The duplicates list in the ordering and representation described above.

json

{
  "input": {
    "classes": "a\tb a  "
  },
  "output": {
    "result": {
      "tokens": [
        "a",
        "b",
        "a"
      ],
      "duplicates": [
        {
          "key": "a",
          "indexes": [
            0,
            2
          ]
        }
      ]
    }
  }
}

Limitations and assumptions

Positions refer to tokens rather than character offsets. CSS escapes and non-ASCII whitespace are not interpreted as token separators.
All declared input fields are required and unexpected top-level fields are rejected. Numbers must be finite; lists are limited to 128 entries and ordinary text fields to 8,192 UTF-16 code units, with tighter limits where stated.
JSON text inputs must parse within bounded nesting and size limits. Numeric outputs outside the safe finite range are rejected; large exact integer results use decimal strings. Indexes and half-open spans are zero-based unless a rank is explicitly described as one-based.

Alternative or Complementary methods

For actual document behavior, inspect a parsed DOM and the relevant HTML algorithm. These tools transform supplied tokens, observations or coordinates; compare the browser result when parsing or layout matters.

References

Tool behavior and example: HTML Class Token Duplicate Audit — tool.io

Similar or alternative tools

HTML Class Token Difference
Subtract literal HTML class tokens while preserving surviving duplicates and order; CSS selector syntax and case folding are not applied.
HTML Class Token Stable Merge
Merge explicit HTML class attribute strings as stable exact token union after ASCII whitespace tokenization; preserve first token appearance.