bdld_datummaker

Detailed Description

Outline

• Purpose
• Classes
• Description
  • Usage
    • Example 1: Testing of a function

Purpose

Provide a mechanism for easily creating bdld::Datum objects.

Classes

• bdld::DatumMaker: a mechanism for easily creating bdld::Datum objects

See also

Description

This component defines a concrete mechanism, DatumMaker that allows bdld::Datum objects to be created with minimal syntax.

Usage

This section illustrates intended use of this component.

Example 1: Testing of a function

Suppose we want to test a function, numCount, that returns the number of numeric elements in a bdld::Datum array.

First we implement the function:

bdld::Datum numCount(const bdld::Datum arrray)
{
    bdld::DatumArrayRef aRef = arrray.theArray();
 
    int count = 0;
 
    for (bdld::DatumArrayRef::SizeType i = 0; i < aRef.length(); ++i) {
        if (aRef[i].isInteger()   ||
            aRef[i].isInteger64() ||
            aRef[i].isDouble()) {
            ++count;
        }
    }
 
    return bdld::Datum::createInteger(count);
}

Then, within the test driver for numCount, we define a bdld::DatumMaker, and use it to initialize an array to test numCount:

bdld::DatumMaker m(&sa);

Here, we create the array we want to use as an argument to numCount:

bdld::Datum array = m.a(
    m(),
    m(bdld::DatumError(-1)),
    m.a(
        m(true),
        m(false)),
    m(42.0),
    m(false),
    m(0),
    m(true),
    m(bsls::Types::Int64(424242)),
    m.m(
        "firstName", "Bart",
        "lastName",  "Simpson",
        "age",       10
    ),
    m(bdlt::Date(2016, 10, 14)),
    m(bdlt::Time(13, 00, 00, 000)),
    m(bdlt::Datetime(2016, 10, 14, 13, 01, 30, 87)),
    m(bdlt::DatetimeInterval(280, 13, 41, 12, 321)),
    m("foobar")
);

Next we call the function with the array-Datum as its first argument:

bdld::Datum retVal = numCount(array);

Finally we verify the return value:

assert(retVal.theInteger() == 3);