core: Remove str::init_elt

This was added based on my FIXME, but I no longer believe it has a place in
core::str, partly because it doesn't follow current naming conventions, and
partly because it can be immitated with a one liner using str::from_chars and
vec::from_elem. I have replaced the existing uses with said one-liner.

Author: brson

src/libcore/extfmt.rs

@@ -373,7 +373,7 @@ mod rt {
                 let len = str::char_len(s);
                 if len < prec {
                     let diff = prec - len;
-                    let pad = str::init_elt(diff, '0');
+                    let pad = str::from_chars(vec::from_elem(diff, '0'));
                     pad + s
                 } else { s }
             };
@@ -398,7 +398,7 @@ mod rt {
         let mut padchar = ' ';
         let diff = uwidth - strlen;
         if have_flag(cv.flags, flag_left_justify) {
-            let padstr = str::init_elt(diff, padchar);
+            let padstr = str::from_chars(vec::from_elem(diff, padchar));
             ret s + padstr;
         }
         let {might_zero_pad, signed} = alt mode {
@@ -418,7 +418,7 @@ mod rt {
                 false
             }
         };
-        let padstr = str::init_elt(diff, padchar);
+        let padstr = str::from_chars(vec::from_elem(diff, padchar));
         // This is completely heinous. If we have a signed value then
         // potentially rip apart the intermediate result and insert some
         // zeros. It may make sense to convert zero padding to a precision
@@ -427,7 +427,7 @@ mod rt {
         if signed && zero_padding && str::len(s) > 0u {
             let head = str::shift_char(s);
             if head == '+' || head == '-' || head == ' ' {
-                let headstr = str::init_elt(1u, head);
+                let headstr = str::from_chars(vec::from_elem(1u, head));
                 ret headstr + padstr + s;
             }
             else {

src/libcore/str.rs

@@ -20,7 +20,6 @@ export
    push_char,
    concat,
    connect,
-   init_elt,
 
    // Reinterpretation
    as_bytes,
@@ -241,16 +240,6 @@ fn connect(v: [str], sep: str) -> str {
     ret s;
 }
 
-#[doc = "Returns a string of <n_elts> repetitions of <c>, which must be \
-           UTF-8"]
-fn init_elt(n_elts: uint, c: char) -> str {
-  let mut rslt = "";
-  uint::range(0u, n_elts) {|_i|
-      push_char(rslt, c);
-  }
-  rslt
-}
-
 /*
 Section: Adding to and removing from a string
 */