[R] Strange problem with reading a pipe delimited file

[Brian Feeny]

I am trying to read in a pipe delimited file that has rows with varying number of columns, here is my sample data:

A|B|C|D
A|B|C|D|E|F
A|B|C|D|E
A|B|C|D|E|F|G|H|I
A|B|C|D
A|B|C|D|E|F|G|H|I|J

You can see line 6 has 10 columns.  Yet, I can't explain why R does like so:

> test <- read.delim("mypaths4.txt", sep="|", quote=NULL, header=F, colClasses="character")
> test
  V1 V2 V3 V4 V5 V6 V7 V8 V9
1  A  B  C  D               
2  A  B  C  D  E  F         
3  A  B  C  D  E            
4  A  B  C  D  E  F  G  H  I
5  A  B  C  D               
6  A  B  C  D  E  F  G  H  I
7  J                        

You can see it moved "J" to row 7, I don't understand why it is not left in position 6,10.

So, more strange to me, I remove line 1, so my data file contains:

A|B|C|D|E|F
A|B|C|D|E
A|B|C|D|E|F|G|H|I
A|B|C|D
A|B|C|D|E|F|G|H|I|J

and I get a totally different result:

> test <- read.delim("mypaths5.txt", sep="|", quote=NULL, header=F, colClasses="character")
> test
  V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1  A  B  C  D  E  F             
2  A  B  C  D  E                
3  A  B  C  D  E  F  G  H  I    
4  A  B  C  D                   
5  A  B  C  D  E  F  G  H  I   J

what it is that I am doing that is changing the fate of that final "J"?  This is just a basic ASCII text file, pipe delimited as shown.

I have been racking my brain on this for a day!

Brian