Expresses disappointment without being too serious. Shows you had hope, but you're accepting reality. I'd hoped to see her at the party, but no such luck.
Pro Tip 2/3
Conversational Tone
Mostly used in casual conversations and spoken English, rather than in formal writing or speeches. I checked again for your missing keys, no such luck though.
Pro Tip 3/3
Common Pairings
Often follows verbs like 'hoped', 'wanted', or 'expected', referring to an outcome that did not occur. We expected a bonus this year, but no such luck.