Auto-Restore

Automatic English word restoration when typing with Vietnamese input method

What is Auto-Restore?

When typing English words with Telex, some letters are interpreted as Vietnamese diacritics (s → sắc, w → ư, etc.). Auto-Restore automatically detects English patterns and restores the original text when you press Space.

How It Works

Comparison: macOS Telex vs Gõ Nhanh

Input	macOS Telex	Gõ Nhanh
text	têt ❌	text ✅
expect	ễpct ❌	expect ✅
perfect	pềct ❌	perfect ✅
with	ưith ❌	with ✅
tesla	téla ❌	tesla ✅
luxury	lủuy ❌	luxury ✅
case	cáe ❌	case ✅
wow	ươ ❌	wow ✅

No need to switch off Vietnamese mode! Just type normally and press Space.

Detection Patterns

Gõ Nhanh uses 8 intelligent patterns to detect English words:

Pattern 1: Modifier + Consonant

// English: Modifier (s,f,r,x,j) followed by consonant
text  → x + t → English ✓
expect → x + p → English ✓
perfect → f + c → English ✓

// Vietnamese: Modifier + sonorant (m,n,ng,nh)
làm → f + m → Vietnamese ✓
hồng → f + ng → Vietnamese ✓

Pattern 2: W at Start + Consonant

// English: W initial before consonant
water, window, world → W + consonant → English ✓

// Vietnamese: W before sonorant
ưng, ưn → W + sonorant → Vietnamese ✓

Pattern 3: EI Vowel Pair

// English: "ei" combination
their, weird → ei + modifier → English ✓

// Vietnamese: No "ei" diphthong exists

Pattern 4: P Initial + AI

// English: P at word start (rare in Vietnamese)
pair → P + ai + r → English ✓
pain → P + ai + n → English ✓

Pattern 5: W as Final

// English: W at word end
raw, law, saw → vowel + W → English ✓

// Vietnamese: W never appears at end

Pattern 6: F Initial

// English: F at word start
fix, file, focus → F + ... → English ✓

// Vietnamese: Uses PH for /f/ sound
phở, phòng → PH (not F) → Vietnamese ✓

Pattern 7: Modifier + K Ending

// English: K at word end with modifier
risk, disk, task → modifier + K → English ✓

// Vietnamese: K final only in ethnic minority words
Đắk Lắk → Đ + K (ethnic minority) → Vietnamese ✓

Pattern 8: Double Vowel + Tone at End

// English: Doubled vowels like "oo"
looks, took → oo + k → English ✓

// Vietnamese: Different pattern (aa → â)

Manual Restore with ESC

For words that Auto-Restore can’t detect, press ESC after typing:

Type: user
Result: úẻ
Press: ESC
Restored: user ✓

ESC restore only works immediately after typing. Once you move the cursor or type more text, it won’t work.

Limitations

Some English words create valid Vietnamese patterns and can’t be auto-detected:

Word	Telex Result	Reason
mix	mĩ	M + ĩ is valid
box	bõ	B + õ is valid
six	sĩ	S + ĩ is valid

Solution: Press ESC to restore, or temporarily disable Vietnamese mode (⌘+Space).

Technical Implementation

Auto-Restore is implemented in the core engine:

core/src/engine/validation.rs

/// English detection patterns
fn is_likely_english(buffer: &Buffer) -> bool {
    // Pattern 1: Modifier + consonant (not sonorant)
    if has_modifier_before_consonant(buffer) {
        return true;
    }
    
    // Pattern 2: W initial + consonant
    if starts_with_w_consonant(buffer) {
        return true;
    }
    
    // ... 6 more patterns
    
    false
}

Examples

Success Cases (Auto-Restored)

Input          Intermediate    After Space
───────────────────────────────────────────
text           têt             text ✓
expect         ễpct            expect ✓
perfect        pềct            perfect ✓
with           ưith            with ✓
push           púh             push ✓
sort           ót              sort ✓
case           cáe             case ✓
wow            ươ              wow ✓
tesla          téla            tesla ✓
luxury         lủuy            luxury ✓

Failure Cases (Need ESC)

Input    Result    Reason              Solution
──────────────────────────────────────────────────
mix      mĩ        Valid Vietnamese    Press ESC
box      bõ        Valid Vietnamese    Press ESC
six      sĩ        Valid Vietnamese    Press ESC
fix      fĩ        Valid Vietnamese    Press ESC

Configuration

Auto-Restore is always enabled and cannot be disabled. This is by design to provide a seamless bilingual typing experience.

If you prefer to disable Vietnamese input entirely for certain apps, use Per-App Mode instead. See Smart Switching.

Comparison with Other IMEs

Feature	Gõ Nhanh	macOS Telex	UniKey	OpenKey
Auto-Restore English	✅	❌	❌	❌
ESC to Restore	✅	❌	✅	✅
Pattern Detection	8 types	N/A	Basic	Basic
Dictionary Lookup	✅	❌	❌	❌

FAQ

Why doesn't 'mix' auto-restore?

Because “mĩ” (M + ĩ) is a valid Vietnamese syllable. Gõ Nhanh cannot distinguish intent without context. Press ESC to restore manually.

Can I add custom English words?

No, the English dictionary is built into the engine. However, the 8 pattern-based rules catch most common words automatically.

Does it work with VNI?

Yes, Auto-Restore works with both Telex and VNI input methods.

What about proper nouns?

Proper nouns follow the same rules. If they match an English pattern, they’ll be restored. Use ESC for ambiguous cases.

Related Features

Input Methods

Learn about Telex and VNI

Smart Switching

Per-app Vietnamese mode