`foo?.bar.yolo.stop()` - Mixed Nullable & Non-Nullable Call Chain

Language Design
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Case in point, Java expert Trisha Gee at JBCNConf’18:

if (customer?.name?.startsWith("A") == true) { ... }

Then I can use this question mark to basically chain my way through customer, name, startsWith, and if there’s null anywhere there it would just ignore it […] and won’t follow the chain through.

In the context of this discussion, yes: this is how we want to understand ? but it’s a little more subtle than that – in fact, it does follow the chain through! I think the point we’re trying to make above is that the subtlety is surprising.

There’s also the issue I laid out in Is the idiom for checking nullable booleans helpful? in this snippet.