From 176eb14d884940865751c2abe087a20be9462e60 Mon Sep 17 00:00:00 2001
From: arunsrinivasan <aragorn168b@gmail.com>
Date: Sat, 11 Jul 2015 23:19:56 +0200
Subject: [PATCH] Remove check_for_seq as .SDcols understands A:B, #748

@Rick, feel free to include/roll back in case you have other use cases I'm not aware of.
---
 R/check_for_seq.r | 81 -----------------------------------------------
 1 file changed, 81 deletions(-)
 delete mode 100644 R/check_for_seq.r

diff --git a/R/check_for_seq.r b/R/check_for_seq.r
deleted file mode 100644
index 8b1dee2b9..000000000
--- a/R/check_for_seq.r
+++ /dev/null
@@ -1,81 +0,0 @@
-## This file contains 
-##   check_for_seq()  and  convert_to_col_number_and_check_valid()
-## for allowing  .SDcols='b':'d'  and/or  by='g':'k'
-##
-## Todo:  Test against  unquoted column names
-##        can NOT yet handle nested functions,
-##           such as  c('b':'d')  or  do.call(paste, list("V", c(3, 7)))
-
-
-
-check_for_seq <- function(input, x) {
-## If input is of the form
-##      from:to
-## this function will interpret from and to to reference columns
-## from, to can be integers or column names
-## they do NOT need to be of the same type
-##
-## If the input is NOT of the above form, the input is returned unchanged
-##
-
-  arg <- as.list(substitute(input))
-
-  ## if input is not of the expected form, return it unchanged
-  if (!(arg[[1]] == ':' & length(arg) == 3)) 
-    return(input)
-
-  from <- convert_to_col_number_and_check_valid ( arg[[2]], x, showWarnings=TRUE )
-  to   <- convert_to_col_number_and_check_valid ( arg[[3]], x, showWarnings=TRUE )
-
-  return( names(x)[from:to] )
-
-}
-
-
-convert_to_col_number_and_check_valid <- function(cn, x, showWarnings=TRUE) {
-## returns the column number of x corresponding to cn
-## while performing several checks to ensure validity
-##
-## cn : a column name or column number
-##      if it is numeric, then we simply check to ensure it is within seq(x)
-##      if it is factor,  it is coerced to character with optional warning
-##      otherwise, it is presumed a character and any coercian will be done by `==`
-##                 in the line  which(cn == names(x))
-
-
-  ## x must have valid names
-  if (is.null(names(x)))
-    stop ("x must have valid names. They are names(x) is NULL")
-
-  ## if input is.name, we need to deparse it
-  if (is.name(cn))
-    cn <- deparse(cn)
-
-  ## factors are too ambiguous. Do we interpret the character value 
-  if (is.factor(cn)) {
-    if (isTRUE(showWarnings))
-      warning("input is a factor and will be coerced to character")
-    cn <- as.character(cn)
-  }
-
-  ## match to col index number
-  if (is.numeric(cn))
-    col <- cn
-  else 
-    col <- which(cn == names(x))
-
-
-  ## ERROR CHECK: confirm there is one and exactly one match
-  ## --------------- ##
-    extra_error_msg <- "\n\nNOTE: using 'b':'d' is a new feature.\nIf you feel this is error should not have occured, please report it."
-
-    if (! length(col))  ## No Match
-      stop ("'", cn, "' is not a name of a column of the data.table.", extra_error_msg)
-    if (length(col) > 1)  ## More than one match
-      stop ("'", cn, "' matches more than one (", length(col), ") columns of the data.table.\nConsider using make.names()", extra_error_msg)
-    if (!any(col == seq(x))) ## outside range of x
-      stop ("'", cn, "' is byeond the range of the seq(x) which is from (1:", length(x), ").", extra_error_msg)
-  ## --------------- ##
-
-  return(col)
-}