/warn
Specifies warning level.
/warn:option
Arguments
option
The minimum warning level you want displayed for the build. Valid values are 0-4:Warning level
Meaning
0
Turns off emission of all warning messages; display errors only.
1
Displays errors and severe warning messages.
2
Displays all errors and level 1 warnings plus certain, less-severe warnings, such as warnings about hiding class members.
3
Displays errors, level 1 and 2 warnings, plus certain, less-severe warnings, such as warnings about expressions that always evaluate to true or false.
4
Displays all errors, level 1-3 warnings, plus informational warnings. This is the default warning level at the command line.
Remarks
The /warn option specifies the warning level for the compiler to display.
Use /warnaserror to treat all warnings as errors up to the warning level specified. Higher-level warnings are ignored.
The compiler always displays errors.
/w is the short form of /warn.
Example
Compile in.js and have the compiler only display level 1 warnings:
jsc /warn:1 in.js