function-student-scores.taq

$ java -jar taq.jar function-student-scores

Running query marks in global scope 
student_marks(report=George english:b+ maths:b- history:a-)
student_marks(report=Sarah english:c+ maths:a history:b+)
student_marks(report=Amy english:b maths:a- history:e+)

Description

function-student-scores.taq demonstrates a function which returns an axiom list declared as an “alpha_grades” template archetype. Each axiom in this list has a “subject” term and a “mark” term. Both values are derived from an integer term with a subject name and in this example there are 3 subjects passed as function parameters - english, maths and history.

template<axiom> alpha_grades (string subject, string mark)

Note how the provider is declared is in the “school’ scope and the provider Java class is specified as a”provider” scope parameter.

scope school(provider = “school.SchoolFunctionProvider”)

The function is declared inside this scope as returning an “alpha_grades” list.

axiom<alpha_grades> function convert_grades(integer marks…)

Also note how the list returned from the function call is assigned to a cursor with the same name as the function

cursor<axiom> convert_grades

$ template<axiom> alpha_grades (string subject, string mark)

scope school(provider = "school.SchoolFunctionProvider") {

function axiom<alpha_grades> convert_grades( integer marks... )

}

flow score
{

export list<axiom> student_marks,
string student

}
(

flow school.convert_grades(english, maths, history) {

cursor<axiom> convert_grades,
list<term> items,
string report = student,
{ ?? (items = convert_grades++)

report += " " + items->subject + ":" + items->mark },

student_marks += axiom { report }

}

)

query marks(grades : score)

axiom list grades
(student, english, maths, history)
{"George", 15, 13, 16}
{"Sarah", 12, 17, 15}
{"Amy", 14, 16, 6}