Humanizr/Humanizer · error · ArgumentException

Unrecognized number word: {unrecognizedWord}

Error message

Unrecognized number word: {unrecognizedWord}

What it means

VigesimalCompoundWordsToNumberConverter.Convert throws this ArgumentException at line 15 when TryConvert cannot parse the phrase under the base-20 + scale grammar. It serves languages combining vigesimal (base-20) constructions with ordinary scale words. Only Convert raises it; the Try overloads return false with the unrecognized token.

Source

Thrown at src/Humanizer/Localisation/WordsToNumber/VigesimalCompoundWordsToNumberConverter.cs:15

namespace Humanizer;

/// <summary>
/// Parses languages that combine base-20 constructions with ordinary scale words.
/// </summary>
internal class VigesimalCompoundWordsToNumberConverter(VigesimalCompoundWordsToNumberProfile profile) : GenderlessWordsToNumberConverter
{
    readonly VigesimalCompoundWordsToNumberProfile profile = profile;

    /// <inheritdoc />
    public override long Convert(string words)
    {
        if (!TryConvert(words, out var parsedValue, out var unrecognizedWord))
        {
            throw new ArgumentException($"Unrecognized number word: {unrecognizedWord}");
        }

        return parsedValue;
    }

    /// <inheritdoc />
    public override bool TryConvert(string words, out long parsedValue) =>
        TryConvert(words, out parsedValue, out _);

    /// <inheritdoc />
    public override bool TryConvert(string words, out long parsedValue, out string? unrecognizedWord)
    {
        if (string.IsNullOrWhiteSpace(words))
        {
            throw new ArgumentException("Input words cannot be empty.");
        }

        var normalized = TokenMapWordsToNumberNormalizer.Normalize(words, TokenMapNormalizationProfile.LowercaseReplacePeriodsWithSpaces);

View on GitHub (pinned to ffc2b77c0f)

Solutions

1. Switch to TryToNumber(words, out var n, culture, out var bad) and handle false.
2. Use the reported bad token to correct the phrase or culture.
3. Pre-clean input and confirm the locale matches the phrase's vigesimal grammar.

Example fix

// before
var n = phrase.ToNumber(culture);
// after
if (phrase.TryToNumber(out var n, culture, out var bad))
    Use(n);
else
    Warn($"unrecognized: {bad}");

if (!words.TryToNumber(out var n, culture, out var unrecognized))
    return Result.Fail($"unrecognized token: {unrecognized}");
return Result.Ok(n);

try { var n = words.ToNumber(culture); }
catch (ArgumentException ex) when (ex.Message.StartsWith("Unrecognized number word"))
    { /* handle */ }

When it happens

Trigger: Calling ToNumber with tokens outside the locale's vigesimal compound map; foreign words, misspellings, or unsupported ordinals. Fires at line 15 when TryConvert returns false.

Common situations: Wrong culture for the phrase; user free text; base-20 forms (e.g. French/Danish-style) the map does not cover; leftover punctuation after normalization.

Related errors

• Unrecognized number word: {unrecognizedWord}
• Unrecognized number word: {unrecognizedWord}
• Unrecognized number word: {unrecognizedWord}
• Unrecognized number word: {unrecognizedWord}
• Unrecognized number word: {unrecognizedWord}

AI-assisted analysis of Humanizr/Humanizer@ffc2b77c0f (2026-08-13). Data as JSON: /api/errors/80855387a626c71f. Report an issue: GitHub.