.. _conditionparser-py:

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conditionparser.py
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class ConditionParser(object):
******************************

Class for parsing conditions in model chain into Reverse Polish Notation form.

def __init__(self, expr, validator, name=None):
===============================================

Validator is responsible for providing the matrix indices for all the variable, level and operation definitions used in the condition expression::

    >>> class Lexicon(object):
    ...     def __init__(self):
    ...         pass
    ...     def variable_ind(self, level, variable):
    ...         if variable == 'AGE':
    ...             return (1, variable)
    ...         elif variable == 'PEAT':
    ...             return (1, variable)
    ...         elif variable == 'SC':
    ...             return (1, variable)
    ...         elif variable == 'TS':
    ...             return (1, variable)
    ...         elif variable == 'MAIN_SP':
    ...             return (1, variable)
    ...         elif variable == 'SP':
    ...             return (2, variable)
    ...         elif variable == 'd':
    ...             return (3, variable)
    ...         elif variable[0] == 'X':
    ...             return (1, variable)
    ...         else:
    ...             return (1,'past_thinning')
    ...     def level_ind(self, level):
    ...         return 2
    ...     def is_child(self, level_1, level_2):
    ...         return True
    >>> class XMLObject(object):
    ...     def __init__(self, lexicon):
    ...         self.lexicon = lexicon
    ...         self.errors = []
    ...     def variable_ind(self, level, variable):
    ...         return self.lexicon.variable_ind(level, variable)
    ...     def level_ind(self, level):
    ...         return self.lexicon.level_ind(level)
    ...     def operation_ind(self, operation):
    ...         if operation == 'thinning':
    ...             return 1
    ...         else:
    ...             return 2
    ...     def add_error(self, msg):
    ...         self.errors.append(msg)
    >>> lexicon = Lexicon()
    >>> validator = XMLObject(lexicon)
    >>> from simo.builder.modelchain.conditionparser import ConditionParser
    >>> cp = ConditionParser(validator, 'comp_unit')

Note that normally the Lexicon methods return only indices, but here text is used to illustrate the structure of the parsed output.

def parse(self, expr, vars_to_indices=True, no_children=False):
===============================================================

Parameters ::

    expr -- condition expression, string
    vars_to_incides -- boolean indicating whether the variable names should be transformed to variable indices
    no_childern -- boolean indicating if children of evaluation level should not be accepted (this is needed for model chain conditions)

Parses the SIMO condition expression into a nested list and further into a Reverse Polish notation / Postfix stack::

    >>> s0 = 'comp_unit:AGE gt 1.0'
    >>> c = cp.parse(s0) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS 
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)

    >>> s1 = 'comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0'
    >>> c = cp.parse(s1)
    >>> for i in c: print i # doctest: +ELLIPSIS 
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'SC', True))
    ('value', 4.0)
    ('eq', <function lee at ...>)
    ('group', <function and_ at ...>)

    >>> s2 = '''(comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0)
    ...         or 
    ...         stratum:SP in [1.0, 2.0, 3.0]'''
    >>> c = cp.parse(s2)
    >>> for i in c: print i # doctest: +ELLIPSIS 
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'SC', True))
    ('value', 4.0)
    ('eq', <function lee at ...>)
    ('group', <function and_ at ...>)
    ('data', (2, 'SP', True))
    ('value', [1.0, 2.0, 3.0])
    ('eq', <function in_ at ...>)
    ('group', <function or_ at ...>)

    >>> s3 = '''((comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0) 
    ...         or comp_unit:thinning since_gt 10)'''
    >>> c = cp.parse(s3)
    >>> for i in c: print i # doctest: +ELLIPSIS
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'SC', True))
    ('value', 4.0)
    ('eq', <function lee at ...>)
    ('group', <function and_ at ...>)
    ('op', 1)
    ('value', 10.0)
    ('since', <function sgt at ...>)
    ('group', <function or_ at ...>)

    >>> s4 = '''((comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0) 
    ...          or stratum:SP in [1.0, 2.0, 3.0]) 
    ...         and 
    ...         ((comp_unit:thinning since_gt 10 
    ...          or comp_unit:thinning since_gt comp_unit:past_thinning) 
    ...         or stratum not exists)'''
    >>> c = cp.parse(s4)
    >>> for i in c: print i # doctest: +ELLIPSIS 
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'SC', True))
    ('value', 4.0)
    ('eq', <function lee at ...>)
    ('group', <function and_ at ...>)
    ('data', (2, 'SP', True))
    ('value', [1.0, 2.0, 3.0])
    ('eq', <function in_ at ...>)
    ('group', <function or_ at ...>)
    ('op', 1)
    ('value', 10.0)
    ('since', <function sgt at ...>)
    ('op', 1)
    ('data', (1, 'past_thinning', True))
    ('since', <function sgt at ...>)
    ('group', <function or_ at ...>)
    ('level', 2)
    None
    ('ex', <function n_ext at ...>)
    ('group', <function or_ at ...>)
    ('group', <function and_ at ...>)

    >>> s5 = '''(comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0 
    ...          or stratum:SP in [1.0, 2.0, 3.0]) 
    ...         and 
    ...         (comp_unit:thinning since_gt 10 
    ...          or comp_unit:thinning since_gt comp_unit:past_thinning 
    ...         or stratum not exists)'''
    >>> c = cp.parse(s5)
    >>> for i in c: print i # doctest: +ELLIPSIS 
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'SC', True))
    ('value', 4.0)
    ('eq', <function lee at ...>)
    ('group', <function and_ at ...>)
    ('data', (2, 'SP', True))
    ('value', [1.0, 2.0, 3.0])
    ('eq', <function in_ at ...>)
    ('group', <function or_ at ...>)
    ('op', 1)
    ('value', 10.0)
    ('since', <function sgt at ...>)
    ('op', 1)
    ('data', (1, 'past_thinning', True))
    ('since', <function sgt at ...>)
    ('group', <function or_ at ...>)
    ('level', 2)
    None
    ('ex', <function n_ext at ...>)
    ('group', <function or_ at ...>)
    ('group', <function and_ at ...>)

    >>> s = 'stratum:SP in [2, 5]'
    >>> c = cp.parse(s)
    >>> for i in c: print i # doctest: +ELLIPSIS
    ('data', (2, 'SP', True))
    ('value', [2.0, 5.0])
    ('eq', <function in_ at ...>)

    >>> s = 'stratum:SP not in [2, 5]'
    >>> c = cp.parse(s)
    >>> for i in c: print i # doctest: +ELLIPSIS
    ('data', (2, 'SP', True))
    ('value', [2.0, 5.0])
    ('eq', <function nin at ...>)

    >>> s = '''comp_unit:AGE gt 1.0 or comp_unit:SC le 4.0
    ...        or stratum:SP in [1.0, 2.0, 3.0]'''
    >>> c = cp.parse(s)
    >>> for i in c: print i # doctest: +ELLIPSIS 
    ('data', (1, 'AGE', True))
    ('value', 1.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'SC', True))
    ('value', 4.0)
    ('eq', <function lee at ...>)
    ('group', <function or_ at ...>)
    ('data', (2, 'SP', True))
    ('value', [1.0, 2.0, 3.0])
    ('eq', <function in_ at ...>)
    ('group', <function or_ at ...>)
    >>> s ='comp_unit:AGE exists'
    >>> c = cp.parse(s)
    >>> for i in c: print i # doctest: +ELLIPSIS
    ('data', (1, 'AGE', True))
    None
    ('ex', <function ext at ...>)

    >>> s = 'tree:d gt self:d'
    >>> c = cp.parse(s)
    >>> for i in c: print i # doctest: +ELLIPSIS 
    ('data', (3, 'd', True))
    ('data', (3, 'd', False))
    ('eq', <function gte at ...>)
    >>> cp.validator.errors
    []
    >>> cp.validator.errors = []

    >>> s = 'tree:d exists'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (3, 'd', True))
    None
    ('ex', <function ext at ...>)
    
    >>> s = 'function:random_number_0_1 lt 2.0'
    >>> c = cp.parse(s)
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS    
    ('function', <function random_number_0_1 at ...>)
    ('value', 2.0)
    ('eq', <function lte at ...>)

This condition is invalid as the variable level (stratum) is a child level of current evaluation level (comp_unit) ::

    >>> s0 = 'stratum:SP eq 1'
    >>> c = cp.parse(s0, no_children=True) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (2, 'SP', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    >>> cp.validator.errors
    ["variable 'stratum:SP' cannot be in 'comp_unit' level condition"]
    >>> cp.validator.errors = []

Examples on how parenthesis affect (or do not affect) the parsed postfix structure ::

    >>> s = '(comp_unit:SC eq 1 and comp_unit:PEAT eq 2) and (comp_unit:TS gt 1100 and comp_unit:MAIN_SP eq 3)'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'SC', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'PEAT', True))
    ('value', 2.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'TS', True))
    ('value', 1100.0)
    ('eq', <function gte at ...>)
    ('data', (1, 'MAIN_SP', True))
    ('value', 3.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function and_ at ...>)

    >>> s = 'comp_unit:SC eq 1 and comp_unit:PEAT eq 2 and comp_unit:TS gt 1100 and comp_unit:MAIN_SP eq 3'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'SC', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'PEAT', True))
    ('value', 2.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'TS', True))
    ('value', 1100.0)
    ('eq', <function gte at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'MAIN_SP', True))
    ('value', 3.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)

    >>> s = '((comp_unit:SC eq 1 and comp_unit:PEAT eq 2) and comp_unit:TS gt 1100) and comp_unit:MAIN_SP eq 3'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'SC', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'PEAT', True))
    ('value', 2.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'TS', True))
    ('value', 1100.0)
    ('eq', <function gte at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'MAIN_SP', True))
    ('value', 3.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)

    >>> s = '(comp_unit:X1 eq 1) or \
    ...      (comp_unit:X2 eq 2 and comp_unit:X3 eq 3) or \
    ...      (comp_unit:X4 eq 4 and comp_unit:X5 eq 5 and comp_unit:X6 eq 6 and comp_unit:X7 eq 7) or \
    ...      (comp_unit:X8 eq 8 and comp_unit:X9 eq 9 and comp_unit:X10 eq 10) or \
    ...      (comp_unit:X11 eq 11 and comp_unit:X12 eq 12 and comp_unit:X13 eq 13)'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'X1', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X2', True))
    ('value', 2.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X3', True))
    ('value', 3.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X4', True))
    ('value', 4.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X5', True))
    ('value', 5.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X6', True))
    ('value', 6.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X7', True))
    ('value', 7.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X8', True))
    ('value', 8.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X9', True))
    ('value', 9.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X10', True))
    ('value', 10.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X11', True))
    ('value', 11.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X12', True))
    ('value', 12.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X13', True))
    ('value', 13.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)

    >>> s = '(comp_unit:X1 eq 1) or \
    ...      (comp_unit:X2 eq 2 and comp_unit:X3 eq 3) or \
    ...      (((comp_unit:X4 eq 4 and comp_unit:X5 eq 5) and comp_unit:X6 eq 6) and comp_unit:X7 eq 7) or \
    ...      ((comp_unit:X8 eq 8 and comp_unit:X9 eq 9) and comp_unit:X10 eq 10) or \
    ...      ((comp_unit:X11 eq 11 and comp_unit:X12 eq 12) and comp_unit:X13 eq 13)'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'X1', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X2', True))
    ('value', 2.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X3', True))
    ('value', 3.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X4', True))
    ('value', 4.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X5', True))
    ('value', 5.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X6', True))
    ('value', 6.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X7', True))
    ('value', 7.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X8', True))
    ('value', 8.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X9', True))
    ('value', 9.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X10', True))
    ('value', 10.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X11', True))
    ('value', 11.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X12', True))
    ('value', 12.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X13', True))
    ('value', 13.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    
    >>> s = 'comp_unit:open_area eq 0 and \
    ...      (comp_unit:USE_RESTRICTION_HARVEST eq 0 or \
    ...      (comp_unit:USE_RESTRICTION_HARVEST in [5, 6, 7, 8, 9] and \
    ...      (comp_unit:year gt comp_unit:USE_RESTRICTION_UNTIL_YEAR or \
    ...      (comp_unit:year eq comp_unit:USE_RESTRICTION_UNTIL_YEAR and \
    ...      comp_unit:month gt comp_unit:USE_RESTRICTION_UNTIL_MONTH) or \
    ...      (comp_unit:year eq comp_unit:USE_RESTRICTION_UNTIL_YEAR and \
    ...      comp_unit:month eq comp_unit:USE_RESTRICTION_UNTIL_MONTH and \
    ...      comp_unit:day gt comp_unit:USE_RESTRICTION_UNTIL_DAY))))'
	>>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'past_thinning', True))
    ('value', 0.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'past_thinning', True))
    ('value', 0.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'past_thinning', True))
    ('value', [5.0, 6.0, 7.0, 8.0, 9.0])
    ('eq', <function in_ at ...>)
    ('data', (1, 'past_thinning', True))
    ('data', (1, 'past_thinning', True))
    ('eq', <function gte at ...>)
    ('data', (1, 'past_thinning', True))
    ('data', (1, 'past_thinning', True))
    ('eq', <function eee at ...>)
    ('data', (1, 'past_thinning', True))
    ('data', (1, 'past_thinning', True))
    ('eq', <function gte at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'past_thinning', True))
    ('data', (1, 'past_thinning', True))
    ('eq', <function eee at ...>)
    ('data', (1, 'past_thinning', True))
    ('data', (1, 'past_thinning', True))
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'past_thinning', True))
    ('data', (1, 'past_thinning', True))
    ('eq', <function gte at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('group', <function and_ at ...>)

    >>> s = '(comp_unit:X1 eq 1) or \
    ...      (comp_unit:X2 eq 2 and comp_unit:X3 eq 3) or \
    ...      ((comp_unit:X4 eq 4 and comp_unit:X5 eq 5) and (comp_unit:X6 eq 6 and comp_unit:X7 eq 7)) or \
    ...      ((comp_unit:X8 eq 8 and comp_unit:X9 eq 9) and comp_unit:X10 eq 10) or \
    ...      ((comp_unit:X11 eq 11 and comp_unit:X12 eq 12) and comp_unit:X13 eq 13)'
    >>> c = cp.parse(s) 
    >>> for i in c: 
    ...     print i # doctest: +ELLIPSIS
    ('data', (1, 'X1', True))
    ('value', 1.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X2', True))
    ('value', 2.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X3', True))
    ('value', 3.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X4', True))
    ('value', 4.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X5', True))
    ('value', 5.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X6', True))
    ('value', 6.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X7', True))
    ('value', 7.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X8', True))
    ('value', 8.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X9', True))
    ('value', 9.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X10', True))
    ('value', 10.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)
    ('data', (1, 'X11', True))
    ('value', 11.0)
    ('eq', <function eee at ...>)
    ('data', (1, 'X12', True))
    ('value', 12.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('data', (1, 'X13', True))
    ('value', 13.0)
    ('eq', <function eee at ...>)
    ('group', <function and_ at ...>)
    ('group', <function or_ at ...>)


Failing conditions::
    
    >>> f = 'comp_unit;AGE gt 1.0'
    >>> c = cp.parse(f)
    >>> cp.validator.errors
    ['Error parsing expression "comp_unit;AGE gt 1.0", Expected ":" at char 9, got ";AGE"']
    >>> cp.validator.errors = []
    >>> f = 'comp_unit:AGE gt 1,0'
    >>> c = cp.parse(f)
    >>> cp.validator.errors
    ['Error parsing expression "comp_unit:AGE gt 1,0", Expected end of text at char 18, got ",0"']
    >>> cp.validator.errors = []
    >>> f = 'comp_unit:AGE > 1.0'
    >>> c = cp.parse(f)
    >>> cp.validator.errors
    ['Error parsing expression "comp_unit:AGE > 1.0", Expected Re:(\'gt|ge|eq|ue|le|lt\') at char 14, got ">"']
    >>> cp.validator.errors = []
    >>> f = 'comp_unit:AGE gt 1.0 and comp_unit:SC <= 4.0'
    >>> c = cp.parse(f)
    >>> cp.validator.errors
    ['Error parsing expression "comp_unit:AGE gt 1.0 and comp_unit:SC <= 4.0", Expected Re:(\'gt|ge|eq|ue|le|lt\') at char 38, got "<="']
    >>> cp.validator.errors = []
    >>> f = '''((comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0) 
    ...          or stratum:SP in [1.0, 2.0, 3.0]) 
    ...         and 
    ...         ((comp_unit:thinning since_gt 10 
    ...          or comp_unit:thinning since_gt comp_unit:past_thinning) 
    ...         or stratum not exist)'''
    >>> c = cp.parse(f)
    >>> cp.validator.errors
    ['Error parsing expression "((comp_unit:AGE gt 1.0 and comp_unit:SC le 4.0) or stratum:SP in [1.0, 2.0, 3.0]) and ((comp_unit:thinning since_gt 10 or comp_unit:thinning since_gt comp_unit:past_thinning) or stratum not exist)", Expected ":" at char 186, got "not"']
    >>> cp.validator.errors = []
    >>> f = 'comp_unit:AGE gt 1.0 and SC lt 4.0'
    >>> c = cp.parse(f)
    >>> cp.validator.errors
    ['Error parsing expression "comp_unit:AGE gt 1.0 and SC lt 4.0", Expected ":" at char 28, got "lt"']

def __construct_condition(self, cond):
======================================

Responsible for the actual processing of the parsed nested list into a RPN stack.

def __process_triplet(self, cond):
==================================

Processess the atomic condition of [variable, operator, value] or [variable, operator, variable] or [level, exists operator] or [operation, operator, value] or [operation, operator, variable].

Also recursively calls the _construct_condition to divide the [condition, boolean operator, condition] cases.

def __set_variable(self, dtype, vardef):
========================================
Retrieves the indices needed for 'data', 'op' and 'level' type operands.