R/errorSingleLogical.R

In predictMe: Visualize Individual Prediction Performance

# errorSingleLogical
#
#
errorSingleLogical <- function(try_x) {
    # 4 error cases. The last exit case means: None of the checked errors applied.
    errorCases <- 4
    # 1
    if(length(try_x)!=1) {
        return(
            list(val=1,
                 msg="Function argument requires a single value.",
                 ec=errorCases))
        # 2
    } else if(!is.logical(try_x)) {
        return(
            list(val=2,
                 msg="Function argument requires a character value.",
                 ec=errorCases))
        # 3
    } else if(is.na(try_x)) {
        return(
            list(val=3,
                 msg="Function argument must not be NA.",
                 ec=errorCases))
        # 4 
    } else if(is.null(try_x)) {
        return(
            list(val=4,
                 msg="Function argument must not be NULL.",
                 ec=errorCases))
    } else {
        return(
            list(val=0,
                 msg="errorSingleLogical filed no complaint.",
                 ec=errorCases))
    }
}