问题
I need to set the language_in option on the Closure compiler to prevent the IE8 parse error:
ERROR - Parse error. IE8 (and below) will parse trailing commas in array and object literals incorrectly. If you are targeting newer versions of JS, set the appropriate language_in option.
I did find a post in the closure group relating to this, however, the option is set directly on the java compiler, rather than through one of the build scripts. I need to be able to set it on a build script.
I'm looking at the scripts in closure/bin/build/ and there are several there. I tried adding the option to closure builder, but it failed.
Can someone direct me about how to set this option correctly?
Thank you.
回答1:
Run the Closure Compiler Application with the --help flag to see a description of each flag.
java -jar compiler.jar --help
CommandLineRunner defines the set of allowed values for --language_in:
--language_in
Sets what language spec that input sources conform.
Options: ECMASCRIPT3, ECMASCRIPT5, ECMASCRIPT5_STRICT, ECMASCRIPT6_TYPED (experimental), ECMASCRIPT_2015, ECMASCRIPT_2016, ECMASCRIPT_2017, ECMASCRIPT_NEXT
The LanguageMode enum has a bit more detail about these values.
Using Closure Builder, the --language_in flag would be passed as an argument to--compiler_flags as in:
--compiler_flags="--language_in=ECMASCRIPT5"
来源：https://stackoverflow.com/questions/13261325/how-can-i-set-the-language-in-option-for-the-closure-compiler