[Grammatica-users] Negation in production rules

[Andrew Smellie]

Hi

I have a very simple grammar that captures data of the form KEY=VALUE

I have written the rule to parse a KEY, but the complexity comes in parsing the 
data. It can span multiple lines, be of arbitrary length and data type (int, 
float, date, string). In fact the only thing you can really say about it is 
that it is not a KEY.

I really want to say something like

KEY=(NOT A KEY)

and parse the three parts (KEY, EQUALS, NOT A KEY) accordingly.

How do I write a production rule that says "not a token"?



I have pasted some of the file below as an example:

DATE="Thu Apr 22 20:41:15 2010"

METHOD=AM1

TITLE="Untitled-1"

KEYWORDS=" AUX AM1 ALLVEC CHARGE=0 COSMO ESP ESR GRAPH HYPERFINE MULLIK POLAR 
SHIFT=80 SPIN"

COMMENTS=""

ATOM_EL[0008]=

C C H H H H H H

ATOM_CORE[0008]=

4 4 1 1 1 1 1 1

ATOM_X:ANGSTROMS[0024]=

-0.3893 0.6545 0.0000

0.3893 -0.6545 0.0000

0.3150 1.5163 0.0000

-1.0344 0.7137 0.9050

-1.0344 0.7137 -0.9050

-0.3150 -1.5163 0.0000

1.0344 -0.7137 0.9050

1.0344 -0.7137 -0.9050

AO_ATOMINDEX[0014]=

1 1 1 1 2 2 2 2 3 4 5 6 7 8

ATOM_SYMTYPE[0014]=

S PX PY PZ S PX PY PZ S S S S S S

AO_ZETA[0014]=

1.8087 1.6851 1.6851 1.6851 1.8087 1.6851 1.6851 1.6851 1.1881 1.1881

1.1881 1.1881 1.1881 1.1881

ATOM_PQN[0014]=

2 2 2 2 2 2 2 2 1 1 1 1 1 1