since I reinstall my R because of the version is high(3.5,what my packages depended is 3.4), whatever I typed, it always shows error on the console. The error message is below. (The first appearance of this error was happened why I install lightgbm package.)
Error in UseMethod("conditionCall") :
no applicable method for 'conditionCall' applied to an object of class "character"
Anyone could give some hints about this error, I don't know how to solve it. Thank you!