Printing Lists

Example:

Convert a StringList object to a String of the form

( element-1 element-2 element-3 ....)

The following code could be used, where a StringBuffer is a standard class (in package java.lang) used to build a new String by appending strings or characters together:

class StringList

{

.... other stuff ....

 

public String toString()

{

StringBuffer b = new StringBuffer();

b.append("(");

StringList L = this;

b.append(first(L));

L = rest(L);

while( !isEmpty(L) )

  {

  b.append(" ");

  b.append(first(L));

  L = rest(L);

  }

b.append(")");

return b.toString();

}