[TxMt] Extra indentation in Markdown mode

[Dr. Drang]

I take class notes on my laptop in Markdown and organize them in a
locally-hosted blog. Last week was the first week I used TextMate
instead of BBEdit for this, and I was occassionaly getting an extra
level of indentation while typing in code blocks. For example, in one
section of my notes I typed this:

|    #include<vector>
|
|    vector<int> v;        // vector of zero elements
|    vector<int> v(250);   // vector of 250 elements, initialized to zero
|    vector<time24> t(10); // 10 elements, all set to 00:00

Each line is indented by four spaces (the pipe characters are meant to
represent the left margin), which Markdown will wrap in <pre> and
<code> tags. I have TM (version 1.5 [906]) set to use soft tabs of 2
characters each.

I found that hitting the Return key after each of these lines (other
than the blank one) would put the cursor on the next line with an
indentation of 6 spaces instead of 4. This may be a red herring, but
the extra indentation seemed to occur only after lines that had an
angle-bracked pair, like <xxx>, in them. So in this excerpt

|    #include<iostream>
|    #include<vector>
|    #include "d_random.h"
|    using namespace std;

the extra indentation occurred after the first two lines, but not
after the second two.

Can anyone tell me why this is happening and what I can do to fix it?

--
Dr. Drang