tunaProgrammingLanguage.txt

The Tuna Programming Language

Purpose

This language is designed specifically to allow automated test of the
CATS robots installed as LS-CAT.  It enables a remote interface to
define and run repeditive tests.  The program state is stored entirely
in a postgresql database server and, although the program is run by a
database client, the interface is simple enough that a client may be
trivially written in any convenient laguage.

Note: Tuna does not stand for anything or have any special
significance.  It's just a name.

Syntax


line: [statement | sqlExpression]

statement: [ START | WHILE booleanExpression | LOOP integerExpression | RETURN ]

START

An implied expression, never explicitly part of any program.  This is
automatically inserted as the first line of the program by
px.tunaInit.

WHILE booleanExpression

Starts a conditional loop.  As long as expression evaluates to the
boolean value of TRUE then execution loops between the WHILE statement
and its corresponding RETURN statement.

LOOP integerExpression

Executes the code between LOOP and RETURN for expression times.  The
expression is evaluated and converted into an integer then compared
with the number of times the loop has already been run.


RETURN

Ends a WHILE or LOOP segment.  A RETURN statement without a corresponding WHILE or LOOP ends the program.


expression:

Any legal SQL query.  SELECT will be prepended to the expression, so
commands such as UPDATE or INSERT or DELETE may only be accessed as
part of a procedural call.  The return value of the expression is ignored.


Support Procedures
All procedures take an argument 'station', meaning that each of the LS-CAT stations lives is a separate space.


void  px.tunaMemorySet( station::bigint, name::text, sqlExpression)
Sets a text variable 'name' using the expression 'sqlExpression'.  Memory is persistant.

text  px.tunaMemoryGet( station::bigint, name::text)
Recalls the value of variable "name"

void px.tunaLoadInit( station::bigint)
Initializes the program space for station.  This must preceed any other tuna programming calls.

void px.tunaLoad( station::bigint, line::text)
Loads "line" as the next line of code

integer px.tunaStep( station::bigint)
Runs the program until
   A) exactly one sqlExpression has been exectuted
or
   B) no sqlExpressions