Parameters

Terminology

• Parameters are elements of tree definitions.
• Arguments are elements of tree invocations.

// parameters 'a' and 'b'
sequence tree(a:string,b:num){
    // arguments 'c', 'd'
    job(c = 1, d = "d")
}

Arguments

Therefore, the arguments represent the attachments of the real value to the parameters. The Argument can be one of two types:

• Named argument
• Unnamed argument

impl action(a:string, b:num)

root main sequnce {
    // Named Arguments
    action(a="a",b:1)
    
    // Unnamed Arguments
    action("a",1)
}

There is impossible to mix named and unnamed arguments The following code will have an error during the compilation process.

impl action(a:string, b:num)
root main sequnce {
    action("a",b=1 )
}

Types

Number

The numbers are defined with a keyword num There are 4 possible types of numbers presented:

• Integers(64)
• Floats(64)
• Hex
• Binary

In case of exceeding the maximum value, the error will be raised on the compile time.

impl action(param:num)

root main sequence {
    // Integers
    action(1)
    action(10e2)
    action(-1)
    action(0)
    
    // Floats
    action(0.0)
    action(100.0e1)
    action(-100.0)
    
    // Hex
    action(0x123)
    
    // Binary
    action(0b010101)
}

String

The strings are defined with string

impl action(param:string)
root main action(param = "X")

Boolean

The booleans are defined with a keyword bool and has the following parameters:

• true for the positive statement
• false for the negative statement

impl action(param:bool);
root main action(true)

Arrays

The arrays are defined with keyword array Arrays can have several aforementioned elements encompassed in one entity.

The arrays have the following syntax:

• [ defines the start of array
• ] defines the end of array
• , defines the separator between elements
• the rest is defined by the particular elements

It is expected, the arrays are homogeneous and have all elements only one type

The arrays can have a trailing comma as well, [1,]

impl action(elems:array);
root main sequence {
    action([1,2,3,4])
    action([1.1,0.1])
    action(["a","b"])
}

Objects

The objects are defined with keyword object Objects can have several aforementioned elements encompassed in one entity with the unique key attached to the every entity

The objects have the following syntax:

• { defines the start of object
• } defines the end of object
• , defines the separator between elements
• "key" defines the name of the element key
• the rest is defined by the particular elements

The objects can have a trailing comma as well, {"a":1,}

impl action(elems:object);
root main sequence {
    action({"key":1, "key2":"key"})
    action(
        {
            "array": [1,2,3,4,],
            "string":"string",
            "num":1,
            "pointer": pointer
        }
    )
}

Tree

The other tree definitions are defined with a keyword tree **The parameters of this type can be added and defined only in the flow definitions.

impl log(id:string,info:string);
cond check();
cond task();

fallback checked_task(check:tree, task:tree){
    check(..)
    task(..)
}

sequence logged_task(id:string, task:tree){
    log(id,"start task")
    task(..)
    log(id,"end task")
}

root main sequence {
    // invoke the task parameter, passing the invokations with parameters 
    logged_task(
        "1",
        // invoke the task, passing the invokations with parameters
        checked_task(check = check(), task())
    )
}

Pointers

Pointers are identifiers of the objects in the BlackBoard Therefore, they can be used to obtain the value of the cell from bb, in argument invoking.

In the example below, the system expects to find a string value in the cell with a name bb_key.

impl action(value:string);

root main sequence {
    // this is a pointer to a cell in bb with an id 'bb_key'
    action(bb_key) 
}

Any

The any type is a special type that can be used to pass any type of value to the parameter.

The type any can take any message type except call

The intention to provide a simple way to generalize the parameters and pass any type of value to the parameter.

// can take anything except call
impl action(value:any);

root main sequence {
    
    action(1) 
    action("a") 
    action([1]) 
}