Re-re-reading it, you'd expect substr(...)=expr to return what the substr was set to. In this case, it returns the value of the substr after the operation was complete. Your 4-argument, err, argument does seem to be the most persuasive.

Bug? Feature? Undefined behavior? I think a case could be made for the validity of either mode of operation.

In reply to Re^2: [substr] anomaly or mine? by tadman
in thread [substr] anomaly or mine? by BrowserUk

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