SyntaxError: catch variable already exists

[kommen]

This seems unexpected to me. Is it?

mqjs --eval "try {} catch (A) {}; try {} catch (A) {}"

results in

SyntaxError: catch variable already exists
    at <cmdline>:1:36

[borkdude]

This is also an interesting difference with other JS engines:

try {} catch (A) {}
console.log(A);

mqjs will log undefined but e.g. Node will crash with the error that A is not defined.

[kommen]

Context: I'm seeing if I can get ClojureScript apps compiled with targeting ecmascript5 running with mquickjs, but the advanced optimized ecmascript5 output contains lots of these constructs.

[bellard]

It works as explained in the documentation i.e. catch variables are declared as normal variables. In order to reduce the possibility of problems, an error is issued if the variable is already declared.

It seems possible to be 100% compatible with JS without adding much complexity so I'll try to fix the issue ASAP.