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Analyzing a structured text file in python

I need to parse text files similar to the ones below using Python, build a hierarchical structure of data objects, and then process them. This is very similar to what we can do with xml.etree.ElementTree and other XML parsers.

The syntax of these files, however, is not XML, and I wonder how best to implement such a parser: if you are trying to subclass one XML parser (which one?) And configure its behavior for tag recognition, write a custom parser, etc.

{NETLIST topblock
{VERSION 2 0 0}

{CELL topblock
    {PORT gearshift_h vpsf vphreg pwron_h vinp vref_out vcntrl_out gd meas_vref 
      vb vout meas_vcntrl reset_h vinm }
    {INST XI21/Mdummy1=pch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/pch_18_mac" Length=0.152 NFIN=8 }
    {PIN vpsf=SRC gs_h=DRN vpsf=GATE vpsf=BULK }}
    {INST XI21/Mdummy2=nch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/nch_18_mac" Length=0.152 NFIN=5 }
    {PIN gs_h=SRC gd=DRN gd=GATE gd=BULK }}
    {INST XI20/Mdummy1=pch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/pch_18_mac" Length=0.152 NFIN=8 }
    {PIN vpsf=SRC gs_hn=DRN vpsf=GATE vpsf=BULK }}
    {INST XI20/Mdummy2=nch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/nch_18_mac" Length=0.152 NFIN=5 }
    {PIN gs_hn=SRC gd=DRN gd=GATE gd=BULK }}
    {INST XI19/Mdummy1=pch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/pch_18_mac" Length=0.152 NFIN=8 }
    {PIN vpsf=SRC net514=DRN vpsf=GATE vpsf=BULK }}
    {INST XI19/Mdummy2=nch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/nch_18_mac" Length=0.152 NFIN=5 }
    {PIN net514=SRC gd=DRN gd=GATE gd=BULK }}
    {INST XI21/MN0=nch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/nch_18_mac" Length=0.152 NFIN=5 }
    {PIN gd=SRC gs_h=DRN gs_hn=GATE gd=BULK }}
    {INST XI21/MP0=pch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/pch_18_mac" Length=0.152 NFIN=8 }
    {PIN vpsf=SRC gs_h=DRN gs_hn=GATE vpsf=BULK }}
    {INST XI20/MN0=nch_18_mac {TYPE MOS} {PROP n="sctg_inv1x/nch_18_mac" Length=0.152 NFIN=5 }
...
}
}
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2 answers

: . , , . , , Parcon:

from pprint import pprint
from parcon import (Forward, SignificantLiteral, Word, alphanum_chars, Exact,
                    ZeroOrMore, CharNotIn, concat, OneOrMore)

block = Forward()
hyphen = SignificantLiteral('"')
word = Word(alphanum_chars + '/_.)')
value = word | Exact(hyphen + ZeroOrMore(CharNotIn('"')) + hyphen)[concat]
pair = word + '=' + value
flag = word
attribute = pair | flag | block
head = word
body = ZeroOrMore(attribute)
block << '{' + head + body  + '}'
blocks = OneOrMore(block)

with open('<your file name>.txt') as infile:
    pprint(blocks.parse_string(infile.read()))

:

[('NETLIST',
  ['topblock',
   ('VERSION', ['2', '0', '0']),
   ('CELL',
    ['topblock',
     ('PORT',
      ['gearshift_h',
       'vpsf',
       'vphreg',
       'pwron_h',
       'vinp',
       'vref_out',
       'vcntrl_out',
       'gd',
       'meas_vref',
       'vb',
       'vout',
       'meas_vcntrl',
       'reset_h',
       'vinm']),
     ('INST',
      [('XI21/Mdummy1', 'pch_18_mac'),
       ('TYPE', ['MOS']),
       ('PROP',
        [('n', '"sctg_inv1x/pch_18_mac"'),
         ('Length', '0.152'),
         ('NFIN', '8')]),
       ('PIN',
        [('vpsf', 'SRC'),
         ('gs_h', 'DRN'),
         ('vpsf', 'GATE'),
         ('vpsf', 'BULK')])]),
     ('INST',
        ...
+3

, , . -, : Piron-based Verilog Parser ( Netlist)

- , , , , pyparsing. XML- .

+4

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