Firefox/Chrome: {} + {} etc.

Allen Wirfs-Brock allen at
Fri Jan 27 10:03:49 PST 2012

On Jan 27, 2012, at 8:38 AM, Luke Hoban wrote:

> JS REPLs tend to parse input as Program productions.  Parsing "{} + {}" as a block followed by a unary expression is correct according to ES5 grammar for Program.  IE behaves the same.  

It's not just in Program, it's any statement context.  However, it is hard to actually observe outside of a REPL.  Try this variant

function f() {
   {;} + {}

to more clearly see what is being parsed.

{ } + {}

clearly belongs in anybodies wtfjs list


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