>Correct documentation is
>

>
>PADL(eExpression, nResultSize [, cExpression])
>
>PADR(eExpression, nResultSize [, cExpression])
>
>PADC(eExpression, nResultSize [, cExpression])
>
>? "Result: " + padl( '', 5, "#_" ) && Result: "#_#_#"
>
>* The implementation have a bug
>? "Result: " + padR( '', 5, "#_" ) && Result: "#_#_#"  Expected "_#_#_"
>

Your expectation is wrong. This is actually implemented as

stuff(left(replicate(cExpression, ceiling(nResultSize/len(cExpression)), nResultsize);
   transform(eExpression), nResultSize-len(transform(eExpression), ;
   len(transform(eExpression))

I.e. VFP repeats the cExpression as needed, then trims it to nResultSize, then stuffs the eExpression in its left, middle or right.