Search argument syntax

>>-+----------------------+--+-------------------------+-------->
   '-RESULT LIMIT--number-'  '-EXPANSION LIMIT--number-'   

>--+------------------------------------------+----------------->
   '-STOP SEARCH AFTER--number--+-DOCUMENT--+-'   
                                '-DOCUMENTS-'     

>--+-| boolean-search-expression |-+---------------------------><
   '-| freetext-argument |---------'   

Boolean-search-expression

|--+-| search-term |-------------------------------------------------+--|
   '-| boolean-search-expression |--| operator-or |--| search-term |-'   

search-term

|--+-| search-factor |-----------------------------------------------+--|
   +-| search-term |--| operator-and |--| search-factor |------------+   
   +-| search-term |--| operator-accum |--| search-factor |----------+   
   '-| search-term |--| operator-minus |--| positive-search-factor |-'   

Search-factor

|--+-----+--| positive-search-factor |--------------------------|
   '-NOT-'                               

Positive-search-factor

|--+-+------------------------------------------------------------+--| search-primary |-+--|
   | |                  .-,----------------------------------.    |                     |   
   | |                  V                                    |    |                     |   
   | '-+-SECTION--+--(----"section-name"--+----------------+-+--)-'                     |   
   |   '-SECTIONS-'                       '-WEIGHT--number-'                            |   
   '-attribute-factor-------------------------------------------------------------------'   

Search-primary

|--+-| text-literal |--------------------+----------------------|
   +-| context-condition |---------------+   
   +-| thesaurus-invocation |------------+   
   +-(--| boolean-search-expression |--)-+   
   '-(--| text-literal-list |--)---------'   

Operator-and

|--&------------------------------------------------------------|

Operator-or

|--|------------------------------------------------------------|

Operator-accum

|--ACCUM--------------------------------------------------------|

Operator-minus

|--MINUS--------------------------------------------------------|

Context-condition

|----| context-argument |--| IN SAME |--| context-unit |--| AS |--| context-argument |---->

>--+-------------------------------+----------------------------|
   | .---------------------------. |   
   | V                           | |   
   '---AND--| Context-argument |-+-'   

Context-argument

|--+-| text-literal |------------+------------------------------|
   +-(--| text-literal-list |--)-+   
   '-| thesaurus-invocation |----'   

Text-literal-list

   .-,------------.   
   V              |   
|----text-literal-+---------------------------------------------|

Context-unit

|--+-PARAGRAPH-+------------------------------------------------|
   '-SENTENCE--'   

Text-literal

|--+--------------------------------+--+----------------+------->
   +-PRECISE FORM OF----------------+  '-WEIGHT--number-'   
   +-STEMMED FORM OF----------------+                       
   '-FUZZY FORM OF--+-------------+-'                       
                    '-match-level-'                         

>--"word-or-phrase"--+----------------------------+-------------|
                     '-ESCAPE--"escape-character"-'   

thesaurus-invocation

|--THESAURUS--"thesaurus-name"--EXPAND-------------------------->

>--+-+-SYNONYM------------+--TERM OF--| text-literal |-------------------+--|
   | +-RELATED------------+                                              |   
   | '-RELATION--(number)-'                                              |   
   '-+-BROADER--+--TERM OF--| text-literal |--+------------------------+-'   
     '-NARROWER-'                             '-FOR--count--+-LEVEL--+-'     
                                                            '-LEVELS-'       

Attribute-factor

|--ATTRIBUTE--"attribute-name"---------------------------------->

>--+-BETWEEN--valueFrom AND valueTo-+---------------------------|
   +->--valueFROM-------------------+   
   '-<--valueTO---------------------'   

freetext-argument

|--IS ABOUT--+----------+--"word-or-phrase"--------------------->
             '-language-'                     

>--+----------------------------+-------------------------------|
   '-ESCAPE--"escape-character"-'