Literal Key Value Line Parser

Split one literal name-value line at its first caller delimiter; does not trim, unquote or interpret escapes.

Description

Split one literal name-value line at its first caller delimiter; does not trim, unquote or interpret escapes.

A first-delimiter split preserves any later delimiter occurrences inside a value.

When to use this tool

Split one literal name-value line at its first caller delimiter; does not trim, unquote or interpret escapes.

Prepare the supplied line, delimiter 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 line, delimiter. 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.name, result.value. Interpret false, null and empty lists using the distinctions below; they can be valid outputs.

Require nonempty delimiter and its presence in line. Return the substring before its first occurrence as name and everything afterward as value.^[1]

Input field	Meaning and representation	Accepted input
line	line.	Text; at most 8,192 UTF-16 code units, subject to the grammar above
delimiter	delimiter.	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.name	The name value under the stated formula or text convention.
result.value	The value value under the stated formula or text convention.

json

{
  "input": {
    "line": "a=b=c",
    "delimiter": "="
  },
  "output": {
    "result": {
      "name": "a",
      "value": "b=c"
    }
  }
}

Limitations and assumptions

No trimming, escapes, comments or key normalization is applied. Empty name or value is allowed.
Every declared top-level field is required and unexpected fields are rejected. Numeric inputs must be finite; ordinary text fields are bounded to 8,192 UTF-16 code units, with tighter operation-specific limits where stated.
Lists are limited to 128 entries. JSON text must meet bounded size and depth checks, and numeric outputs beyond the safe finite magnitude are rejected. Exact large integers use decimal strings.
Indexes are zero-based and spans have an exclusive end unless explicitly stated otherwise. A valid false, null or empty-list result is distinct from malformed input.

Alternative or Complementary methods

Choose the exact text grammar before combining serializers and parsers. UTF-16 record lengths, raw separators and custom backslash escapes differ from byte framing, CSV, Markdown and spreadsheet semantics.

References

Tool behavior and example: Literal Key Value Line Parser — tool.io

Similar or alternative tools

Literal Key Value Line Formatter
Format a literal name-value line while rejecting delimiters inside its name to retain first-split reversibility.
Key Value Block Duplicate Audit
Audit duplicate literal keys in an ordered key-value block without choosing first or last wins.