Fix deprecation warnings due to bytestring()

Also improve a few docstrings and simplify code using @sprintf.

src/abstractdataframe/show.jl

@@ -7,20 +7,19 @@
 #'
 #' @param df::AbstractDataFrame The AbstractDataFrame to be summarized.
 #'
-#' @returns res::UTF8String The summary of `df`.
+#' @returns res::String The summary of `df`.
 #'
 #' @examples
 #'
 #' summary(DataFrame(A = 1:10))
-function Base.summary(df::AbstractDataFrame) # -> UTF8String
+function Base.summary(df::AbstractDataFrame) # -> String
     nrows, ncols = size(df)
-    return utf8(@sprintf("%d×%d %s", nrows, ncols, typeof(df)))
+    return @sprintf("%d×%d %s", nrows, ncols, typeof(df))
 end
 
 #' @description
 #'
-#' Determine the number of UTF8 characters that would be used to
-#' render a value.
+#' Determine the number of characters that would be used to print a value.
 #'
 #' @param x::Any A value whose string width will be computed.
 #'
@@ -139,7 +138,7 @@ end
 #' @description
 #'
 #' Given the maximum widths required to render each column of an
-#' AbstractDataFrame, this returns the total number of UTF8 characters
+#' AbstractDataFrame, this returns the total number of characters
 #' that would be required to render an entire row to an IO system.
 #'
 #' NOTE: This width includes the whitespace and special characters used to

src/dataframe/io.jl

@@ -499,7 +499,7 @@ function bytestotype{N <: AbstractString,
         return "", true, true
     end
 
-    return bytestring(bytes[left:right]), true, false
+    return String(bytes[left:right]), true, false
 end
 
 function builddf(rows::Integer,
@@ -560,12 +560,9 @@ function builddf(rows::Integer,
                 if wasparsed
                     continue
                 else
-                    msgio = IOBuffer()
-                    @printf(msgio,
-                            "Failed to parse '%s' using type '%s'",
-                            bytestring(p.bytes[left:right]),
-                            o.eltypes[j])
-                    error(bytestring(msgio))
+                    error(@sprintf("Failed to parse '%s' using type '%s'",
+                                   String(p.bytes[left:right]),
+                                   o.eltypes[j]))
                 end
             end
 
@@ -682,7 +679,7 @@ function parsenames!(names::Vector{Symbol},
             end
         end
 
-        name = bytestring(bytes[left:right])
+        name = String(bytes[left:right])
         if normalizenames
             name = identifier(name)
         end
@@ -712,17 +709,12 @@ function findcorruption(rows::Integer,
     m = median(lengths)
     corruptrows = find(lengths .!= m)
     l = corruptrows[1]
-    msgio = IOBuffer()
-    @printf(msgio,
-            "Saw %d rows, %d columns and %d fields\n",
-            rows,
-            cols,
-            fields)
-    @printf(msgio,
-            " * Line %d has %d columns\n",
-            l,
-            lengths[l] + 1)
-    error(bytestring(msgio))
+    error(@sprintf("Saw %d rows, %d columns and %d fields\n * Line %d has %d columns\n",
+                   rows,
+                   cols,
+                   fields,
+                   l,
+                   lengths[l] + 1))
 end
 
 function readtable!(p::ParsedCSV,