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Comment by matusp | Hacker News Reader

People raging over the ternary operation in Python should learn to use:

  x = {True: 5, False: 4}[condition()]

, or if you don't want to evaluate the values:

  x = {True: lambda: 5, False: lambda: 4}[condition()]()

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This is perhaps one of the most obscure ways to do ternaries I could have thought of, and while it really is quite clever, I think I'd be pretty annoyed if I encountered it in the wild.

    x = (4, 5)[condition()]

for a bonus "what am I looking at again?"

This pattern also nicely expands when you need to select from more than 2 values. And it lets you keep the mapping as a data instead of turning it into logic.

  {"a": 1, "b": 2}.get(selector(), default_value)

for the else-case.

Brilliant.

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