Common Font Ligature Count Lookup
Independently font/version/feature-specific ligature inventory count, not assumed common font constant. Exact independently documented reference matching, signed discrepancy retained. Explicit caller font/layout/reference context; not a shaping engine, actual page layout or accessibility certification.
Description
A ligature inventory is specific to a font version and selected features.
A ligature inventory is specific to a font version and selected features.1
Comparing an observed count with a keyed reference avoids assuming that common font names imply fixed counts.
When to use Common Font Ligature Count Lookup
Use this tool when you need to compare an observation with a matched numeric reference. Establish the font version, feature, layout, physical or CSS units, and matched reference basis needed for this calculation.
How to use Common Font Ligature Count Lookup and understand its results
- Establish the font version, feature, layout, physical or CSS units, and matched reference basis needed for this calculation.
- Enter callerVerifiedFontLigatureInventoryKeys, callerVerifiedFontLigatureInventoryValues, queryFontLigatureInventoryKey, observedFontLigatureInventoryValue, following the field table and rules below, then run the tool.
- Read callerReferenceValue, signedObservedMinusReference. Use the output meanings below to interpret units, signs, flags, and any nested result fields.
- Correct reported input issues and run again. For a successful result, check the stated evidence coverage and assumptions before using it in your review.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| callerVerifiedFontLigatureInventoryKeys | Caller verified font ligature inventory keys | list of string | Required |
| callerVerifiedFontLigatureInventoryValues | Caller verified font ligature inventory values | list of number | Required |
| queryFontLigatureInventoryKey | Query font ligature inventory key | string | Required |
| observedFontLigatureInventoryValue | Observed font ligature inventory value | number | Required |
Provide unique nonblank reference keys, aligned numeric reference values, an exact query key, and an observed numeric value in the same unit and method. Return the matched reference value and observed minus reference. Matching is case-sensitive with no trimming or normalization; unknown keys cause an input error. A negative discrepancy means the observation is below the supplied reference.
reference=values[indexOf(keys,query)]; discrepancy=observed−reference Symbols follow the input and output meanings and the calculation rules above.
All reference counts and the observed count must be nonnegative safe integers.
| Output field | Meaning | Value type |
|---|---|---|
| callerReferenceValue | Caller reference value | number |
| signedObservedMinusReference | Signed observed minus reference | number |
{
"input": {
"callerVerifiedFontLigatureInventoryKeys": [
"a",
"b"
],
"callerVerifiedFontLigatureInventoryValues": [
2,
4
],
"queryFontLigatureInventoryKey": "b",
"observedFontLigatureInventoryValue": 5
},
"output": {
"callerReferenceValue": 4,
"signedObservedMinusReference": 1
}
}Limitations and assumptions
This is a user-supplied catalog comparison, with no embedded complete reference table or live update. You must establish matching units, method, specimen or font identity, and edition independently.
Missing required fields, unknown fields, wrong types, and violated calculation rules are input issues. Numeric values must be finite; nonfinite results are rejected. Evidence arrays must be dense, with no missing cells. Numeric observation lists allow at most 10,000 entries, subject to any smaller bounds stated above. String lists allow at most 128 strings of at most 128 characters. Extremely large text is rejected.
Alternative or Complementary methods
For a related review, use Average Kerning Pairs Per Font Lookup: Kerning inventory counts depend on font version and table representation. A keyed reference comparison can audit the declared count without treating class-based GPOS kerning as a simple universal pair list. For a complementary step, use WOFF2 vs TTF Compression Ratio Lookup: Font compression savings need files with the same glyph content and comparable encoding scope. Comparing their measured byte sizes gives a file-size ratio that can also show negative savings.
References
-
Common Font Ligature Count Lookup — tool.io
Similar or alternative tools
- Average Kerning Pairs Per Font Lookup
Kerning inventory counts depend on font version and table representation. A keyed reference comparison can audit the declared count without treating class-based GPOS kerning as a simple universal pair list.
- WOFF2 vs TTF Compression Ratio Lookup
Font compression savings need files with the same glyph content and comparable encoding scope. Comparing their measured byte sizes gives a file-size ratio that can also show negative savings.