[datatable-help] fread with multi-line character vector input

[Douglas Clark]

Can fread read from a multi-line character vector, similar to the read.table
text= argument? Feature request?

I am importing the output "print" file from a dispersion model (a fortran
program). The output file consists of 4000+ lines of text, tables of model
parameters, and tables of model results, all of varying lengths. I read the
entire file into a character vector variable, such as mylines <-
readLines(...), and then use regular expressions to "clean" the text and
locate the starting and ending lines of the tables to be imported.

I tried to use fread(mylines[start:stop]), but fread doesn't accept a vector
of character strings as input -- only a length 1 character vector (ie all in
one string).

read.table does allow reading from a multi-line character vector variable,
using the text= argument, ie read.table(text = mylines[start:stop],...).

fread will also read it, if I collapse the multi-line character vector into
a single string using paste0 or stri_flatten, as in 
  fread(paste0(mylines[start:stop],  collapse = "\n"))
or
  fread(stri_flatten(mylines[start:stop], collapse = "\n"))

But it would be nice if I could skip the collapse step.

Does fread have a way to directly read from a multi-line character vector
without flattening it -- like the text= argument in read.table ?  Or is
there an easier approach? If not, should this be a feature request?



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