Code blocks in ruby are used as method parameters.

The ruby method can accept code blocks as parameters, which is a very flexible method and a very good design idea. Suppose there are three methods as shown in 1:

Figure 1

As shown in figure 1, a large number of code blocks of method A, Method B, and method C are identical. Do you need to define three methods? Is there a better way?
In the software development field, there is an important dry rule: Do not repeat. In the three methods shown in figure 1, we can find that they contain a large number of repeated code. To this end, we combine the above three methods into one method, the specific code block in the three methods is passed as a parameter, as shown in step 2.

Figure 2

As shown in figure 2, you can use a code block as a parameter to replace multiple methods with one method, so as to provide better code reuse and ensure better Software maintainability.

Sample Code:

@ Testdata = array. New
@ Testdata <"Sun Wukong"
@ Testdata <""

Def make (thing)
Puts "Preparations"
Yield (thing)
Puts "receiving action"
End

Def pp (key1, key2)
Puts key1 + "and" + key2
End

Make (@ testdata) {| A |
PP (*)
}

Make ("") {| A |
Puts
}

Make ("Tang Seng") {| A |
Puts
}

Running result:

Preparations

Sun Wukong and pig

Receiving action

Preparations

Pig

Receiving action

Preparations

Tang Seng

Receiving action