8.1 Expression syntax

An expression applies relational operators to simple expressions. Simple expressions are a series of terms (what a term is, is explained below), joined by adding operators.

_________________________________________________________________________________________________________ Expressions
--        -              -|--------------------------------------
  expression  simple expression  |-- *-- simple expression-|
                            -<= |
                            - >-|
                            |>= |
                            | =-|
                            |<> |
                            |in |
                            -is -

--simple expression-|-term ------------------------------------------
                 -|-+ ----
                  |-- --|
                  |-or--|
                  -xor -
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The following are valid expressions:

GraphResult<>grError  
(DoItToday=Yes) and (DoItTomorrow=No);  
Day in Weekend

And here are some simple expressions:

A + B  
-Pi  
ToBe or NotToBe

Terms consist of factors, connected by multiplication operators.

_________________________________________________________________________________________________________ Terms
--term --|-factor-------------------------------------------------
        ----* ----
         -- / --|
         - div --|
         -moandd --|
         --shl--|
         --shr--|
         --as---|
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Here are some valid terms:

2 * Pi  
A Div B  
(DoItToday=Yes) and (DoItTomorrow=No);

Factors are all other constructions:

_________________________________________________________________________________________________________ Factors
--factor--|(- expression -) ----------------------------------------
         -variable reference-|
         -  function call -|
         -unsigned constant--|
         ---nsiogtn- fafacctotror---|
         --set constructor---|
         --value typecast---|
         --address factor--|

--unsigned constant--unsigned number-------------------------------
                  --character string--|
                  -constant identifier -|
                  ------Nil-------|
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