Error in parse(outFile)

[yanwuanxin]

Error in parse(outFile) : /tmp/RtmpafO9XW/Rbuild84c567e69b58/SeuratObject/R/assay5.R:108:13: unexpected input 107: expr = Layers(object = object, search = layer), 108: error = \

[yanwuanxin]

Replace lines 106-109：
layer <- tryCatch( expr = Layers(object = object, search = layer), error = function(e) { expr <- NULL })
but what kind of writing is this？ error = \(...) NULL

[yanwuanxin]

utils.R/ seurat.R/ assay5.R they all have a similar writing style, using "" instead of "functon"; someone answer for me?