How to parse blocks lead by spaces

So, I gave up on VS2015. I've installed 2017 on my desk top for spirit. 
What I'm out to do is parse a decompressed BXL file into my object.
<http://lakeweb.net/content/bxl_output.txt>

Question:
Scoping is done with leading spaces. I've searched but still at a loss 
as to the right way to do it. My first thought is to read leading spaces 
and create an index. The only stuff I want to parse at first is the 
'TextStyle' and 'Symbol' blocks. So skip 'unknown' blocks for now, add 
them later as needed.
~~~~

I do want to avoid semantic actions as much as possible but they may be 
unavoidable. This:
<https://stackoverflow.com/questions/49246414/dynamically-switching-symbol-tables-in-x3/49269239#49269239>

Is one of the best starting points I've found for the likes of what I'm 
after. And from there, an x3::symbols table?? Reason, I am parsing Pins 
now but with the assumption that the order of the sub objects is 
consistent. That I should parse with any order acceptable as I did in 
'extra info'.

~~~~ extra info
It has been a couple of years since I've worked with spirit. Here I 
think I've done a decent job with the front end but the back end became 
quite the ad hoc.

<https://github.com/lakeweb/PCBEdit/blob/master/SpiritParsers.h>
The source file looks like:
<http://lakeweb.net/content/ecc83-pp.kicad_pcb>
pudding proof( not from the same file)
<http://lakeweb.net/content/ScreenShot.png>

Thanks, Dan.


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