Error creating multiple heatmaps with ComplexHeatmap package - r

Question

I am having difficulty with creating multiple heatmaps with the ComplexHeatmap package. When I run a script that contains code exactly lifted from the documentation (https://bioconductor.org/packages/release/bioc/vignettes/ComplexHeatmap/inst/doc/s3.a_list_of_heatmaps.html)...
library(ComplexHeatmap)
mat1 = matrix(rnorm(80, 2), 8, 10)
mat1 = rbind(mat1, matrix(rnorm(40, -2), 4, 10))
rownames(mat1) = paste0("R", 1:12)
colnames(mat1) = paste0("C", 1:10)
mat2 = matrix(rnorm(60, 2), 6, 10)
mat2 = rbind(mat2, matrix(rnorm(60, -2), 6, 10))
rownames(mat2) = paste0("R", 1:12)
colnames(mat2) = paste0("C", 1:10)
ht1 = Heatmap(mat1, name = "ht1")
ht2 = Heatmap(mat2, name = "ht2")
class(ht1)
class(ht2)
ht1 + ht2
... I get the error message:
Error in ht1 + ht2 : non-numeric argument to binary operator
Execution halted
I am running R version 3.3.2 (2016-10-31) -- "Sincere Pumpkin Patch" on Mac OS X 10.12.2 with ComplexHeatmap version 1.12.0. Thank you for any help!

Answer 1

I figured it out. The problem was that the "methods" package needs to be attached. If you run the above code directly in R (which I was NOT doing), it works as-is (becuase R apparently loads the methods package by default), but if you have the script in a file and run it via Rscript (which is what I WAS doing), you get the indicated error. However, If you add
library(methods)
to the top of the script, it works via Rscript.