Feature call auto complete

Overview

EiffelStudio editor provides automatic help for completing feature calls.

With the default EiffelStudio preferences, feature call auto-completion occurs automatically when you type a dot ('.') character after a feature name.

This means, for example, that in the Editor pane when you type: my_string. the editor will propose a list of possible valid feature names from which to choose, as seen in Figure 1.

Feature call auto-completion can also be triggered:

1. By pressing crtl+space
2. By following the edit menu path:

Edit --> Advanced --> Complete word

Feature call auto-completion is most commonly used in the Editor pane. But the same functionality is also available elsewhere in EiffelStudio, for example:

• Expressions in the editable grid of the Watch tool.
• "Expression" in the New Expression dialog of the Watch tool.
• "Condition" in the Breakpoints dialog

The feature call auto-completion window

Using the example above, when auto-completion is triggered, the feature call auto-completion window will pop up and display a list of feature names which can be applied in the current context.

Figure 1. The feature auto-completion window.

When the auto-completion window appears, the first item in the list, if any, will be selected. To complete your code with the selected item, press "Enter" or "Ctrl+Space". To choose another item, use keyboard Up and Down arrows or the mouse.

You can also continue typing characters and the list will automatically be narrowed provided that you have non-matching entries filtered out (see Auto-completion list display options below). So, you can think of the auto-completion as a search for feature names using the characters you type followed by a wild card character, the asterisk ('*'). Of course, you don't have to put the asterisk at the end, it's just always implied. Once you've triggered auto-completion, you can however use the wild card character in the middle of a string, like this:

my_string.a*intwhich would narrow the list to all feature names starting with "a" and also containing the string "int".

To validate your choice, press "Enter" or "Ctrl+Space".

If there is no selected item, the content of the text you have typed will be inserted.

The auto-completion can be cancelled by clicking outside the window or pressing Esc.

Entering routine arguments

After you have selected a feature, if the feature is a routine requiring arguments, the argument prototypes will be included in the generated feature text, and the text for the first argument will be selected, as in Figure 2.

Figure 2. Auto-completion of a routine with arguments.

Because the text for the first argument is already selected, you can go ahead and type a value for that argument. When you've completed the first argument, press Tab, and the next argument will be selected, and you can type a value for it. When you Tab after entering the final argument, the cursor will be positioned after the right parenthesis, so you are ready to move on.

Auto-complete list display options

At the bottom of the auto-completion window you will find a row of icons labeled "Options:". These options help you control which choices are presented to you and the format of their presentation. The options are described in the section on class name auto-completion.

Tip: The following tips can help you get the most out of feature call automatic completion:
1) You can call the auto-complete without an identifier. The auto-complete window will then show the features of the current class.
2) The keyboard shortcut for automatic completion can be changed in the editor preferences.
3) When the auto-completion window is open, typing any character (other than a wild card) that is not ordinarily valid in feature names automatically closes the window. So, you can type '.', ' ' or '(' to close the completion window and start typing the next token straight away.

Note: There are just a few more things you should know about feature call automatic completion:
1) Only identifiers that were already defined when the class was compiled for the last time can be completed, except for local entity names that can always be completed.
2) Only compiled features will appear in the auto-complete window.
3) By default, features from class ANY will be ignored by the auto-complete window. This can be changed in the editor preferences.