Custom Functions with Macros

From the twig documentation, lets go to macro. 0:00 Macros are like writing custom function. 0:04 These functions are different than PHP functions in a few ways. 0:08 Arguments of macro are always optional. 0:12 This means that your not required to define default values 0:16 along with your argument. 0:20 However, you may set a default value when defining an argument. 0:21 You can also set a default value later on in your code, but 0:26 they work a little differently. 0:30 Default argument values are defined using the default filter 0:32 when you're in the macro body. 0:36 If extra positional arguments are passed to a macro, 0:39 they end up in the special varargs variable as a list of values. 0:43 But just like with PHP functions, 0:48 macros only know about the variables that have been passed. 0:51 Let's define a form field macro. 0:55 We'll create a new template. 0:58 Named form.twig. 1:03 And we're going to define a macro, so 1:07 we use our command macro, and we're going to name this input. 1:10 And then I'll end my macro. 1:19 I'm going to paste it in a form field group. 1:22 And we'll start adding fields from there. 1:25 You can check the notes for your own group. 1:27 The most important thing is the name of our form field, so 1:32 let's add that as the first argument of our macro. 1:36 We'll call this name. 1:41 Then I'm going to use the name in a few places. 1:43 First, the name of our field will just be name. 1:49 The idea of our field that we'll use for the for 1:54 in the label, we'll add input and then name. 1:57 So let's add that to the for as well, input and then name. 2:05 Our label itself is going to use name. 2:11 But I want to add the title filter. 2:15 Finally, our placeholder is going to say, Enter your, and then name. 2:20 That's all we really need to do. 2:29 But let's add a few more options. 2:32 We'll want to show the user entered value. 2:34 Then if their was an error or some other problem when the user submitted the form, 2:37 they'll see the value and they won't have to retype it. 2:42 We'll add value. 2:47 And then here in our field, We'll add value. 2:51 By default, twig is escaping our variables. 2:57 But if we want to make extra sure that this variable is escaped, 3:01 we can add an escape filter just to be sure. 3:05 We use the shortcode e for escape. 3:10 Twig won't double escape, so this is going to work just fine. 3:13 We might want to allow a password field. 3:17 So then we will need to be able to change the type, 3:20 so let's add type as an argument. 3:23 By default we want our type to be text, so 3:29 we're going to add type and then default, 3:33 To text, Default. 3:40 Finally, we have some help text that we only want to display if the help is set. 3:49 So first, we need to accept an argument for 3:56 help, and then we're going to display that help here. 3:59 But I also want to set up a conditional. 4:05 If help is not empty. 4:09 Endif. 4:15 Now let's go to the contact page and add our form. 4:18