repl completion inside a def

Why can’t it offer the options for a seemingly trivial line:

C:\Users\razvanc>c:\bin\scala\bin\scala

Welcome to Scala version 2.9.1.final (Java HotSpot(TM) 64-Bit Server VM, Java 1.

6.0_27).

Type in expressions to have them evaluated.

Type :help for more information.

scala> "s".<TAB>

+                     asInstanceOf          charAt

codePointAt           codePointBefore       codePointCount

compareTo             compareToIgnoreCase   concat

contains              contentEquals         endsWith

equalsIgnoreCase      getBytes              getChars

indexOf               intern                isEmpty

isInstanceOf          lastIndexOf           length

matches               offsetByCodePoints    regionMatches

replace               replaceAll            replaceFirst

split                 startsWith            subSequence

substring             toCharArray           toLowerCase

toString              toUpperCase           trim

scala> def x(s:String) = s.<TAB>

-          Nothing here…