Thanks for all votes and insightful answers to the poll on usage of @java's var! Not unexpectly, replies range from "using var all the time" to "don't see the point of it". Yet one third never using var at all was a surprise for me. Some repeating themes from replies in this 🧵.
1⃣ Readability vs. writability: some argued var optimizes for writing code (less characters to type) at the cost of reading code (less explicit type info). I don't think that's the intention behind var. In fact, more (redundant, repetitive) code may read worse.
2⃣ var only or primarily used in test code: described by several folks as a good starting point for getting their feet wet with local variable type inference, before using it more widely.
3⃣ Structural typing: a sweetspot for var. E.g. when dealing with query DSLs returning complexily structured generic types, omitting them can greatly increase readability. Similarly, as @tagir_valeev put it, "'var' instead of 'Iterator<Map.Entry<String, Integer>>' is relieving".
4⃣ Missing support for val: some would like to have this for less verbose declaration of final local variables. This was considered, here's @BrianGoetz's explanation why it wasn't added (immutability more important for fields than local vars): mail.openjdk.java.net/pipermail/plat…
5⃣ var rarely used for anonymous types: being able to declare and reference members of local-scoped anonymous types was discussed with excitement by some back when Java 10 came out. No one mentioned it during this poll; seems like use cases for this are rare after all? 
6⃣ My take-away: readability is key. If explicit variable type declarations provide clarity -- go and add them. If they're more noise than anything -- var is your friend. @stuartmarks' style guide is of great help when making this decision. ~~ Fin ~~
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