Why the the pos must be greater than 0?

[Foreveorjizhi]

In AbstractCompletionProvider.java:
Function: protected List getCompletionsImpl(JTextComponent comp):

Line 184 to 188:
while (pos>0 &&
comparator.compare(completions.get(pos), text)==0) {
retVal.add(completions.get(pos));
pos--;
}

In the loop condition, 'pos' must be greater than 0, but the index of 'completions' includes 0, which will result in never searching the first element. Is that right?