Lamb Linda - Learning the vi and Vim Editors стр 12.

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mode.) If you type 200 characters before pressing ENTER , vi regards all 200 characters

as a single line (even though those 200 characters visibly take up several lines on the

screen).

As we mentioned in Chapter 1, vi has an option that allows you to set a distance from

the right margin at which vi will automatically insert a newline character. This option

is wrapmargin (its abbreviation is wm). You can set a wrapmargin at 10 characters:

:set wm=10

This command doesnt affect lines that youve already typed. Well talk more about

setting options in Chapter 7. (This one really couldnt wait!)

If you do not use vis automatic wrapmargin option, you should break lines with carriage

returns to keep the lines of manageable length.

Vim, with nocompatible set, allows you to space past the end of the line to the next one with l or the space

bar.

16 | Chapter 2:Simple Editing

Two useful commands that involve movement within a line are:

0

0 (digit zero)

Move to beginning of line.

$

Move to end of line.

In the following example, line numbers are displayed. (Line numbers can be displayed

in vi by using the number option, which is enabled by typing :set nu in command mode.

This operation is described in Chapter 7.)

1 With a screen editor you can scroll the page,

2 move the cursor, delete lines, insert characters,

and more, while seeing the results of your edits

as you make them.

3 Screen editors are very popular.

The number of logical lines (3) does not correspond to the number of visible lines

$ (5) that you see on the screen. If the cursor were positioned on the d in the word

delete , and you entered $, the cursor would move to the period following the word

them . If you entered 0, the cursor would move back to the letter m in the word move ,

at the beginning of line two.

Movement by Text Blocks

You can also move the cursor by blocks of text: words, sentences, paragraphs,

w etc. The w command moves the cursor forward one word at a time, counting

symbols and punctuation as equivalent to words. The following line shows cursor

movement by w:

cursor, delete lines, insert characters,

You can also move by word, not counting symbols and punctuation, using the W com-

mand. (You can think of this as a large

or capital W ord.)

Cursor movement using W looks like this:

cursor, delete lines, insert characters,

To move backward by word, use the b command. Capital B allows you to move back-

ward by word, not counting punctuation.

As mentioned previously, movement commands take numeric arguments; so, with ei-

ther the w or b commands you can multiply the movement with numbers. 2w moves

forward two words; 5B moves back five words, not counting punctuation.

To move to a specific line, you can use the G command. Plain G goes to the end of the

file, 1G goes to the top of the file, and 42G goes to line 42. This is described in more detail

later in the section The G (Go To) Command on page 43.

Moving the Cursor | 17

With a editor you can scrooll the page,

move the cursor, delete lines, nisret

characters, and more, while results of

your edits as you make tham.

Since they allow you to make changes

as you read through a file, much as

you would edit a printed copy,

screen editors are very popular.

Figure 2-3. Proofreading edits

Well discuss movement by sentences and by paragraphs in Chapter 3. For now,

practice using the cursor movement commands that you know, combining them with

numeric multipliers.

Simple Edits

When you enter text in your file, it is rarely perfect. You find typos or want to improve

on a phrase; sometimes your program has a bug. Once you enter text, you have to be

able to change it, delete it, move it, or copy it. Figure 2-3 shows the kinds of edits you

might want to make to a file. The edits are indicated by proofreading marks.

In vi you can perform any of these edits with a few basic keystrokes: i for insert (which

youve already seen); a for append; c for change; and d for delete. To move or copy text,

you use pairs of commands. You move text with a d for delete, then a p for put;

you copy text with a y for yank, then a p for put. Each type of edit is described in

this section. Figure 2-4 shows the vi commands you use to make the edits marked in

Figure 2-3.

Inserting New Text

You have already seen the insert command used to enter text into a new file. You also

use the insert command while editing existing text to add missing characters, words,

and sentences. In the file practice, suppose you have the sentence:

you can scroll

the page, move the cursor, delete

lines, and insert characters.

18 | Chapter 2:Simple Editing

i screen ESC

x

i seeing the ESC

With a editor you can scrooll the page, cw

move the cursor, delete lines, nisret

insert

characters, and more while results of

ESC

rs

your edits as you make tham.

re

P

Since they allow you to make changes

as you read through a file, much as

you would edit a printed copy,

r.

dd

screen editors are very popular.

x

rS

Figure 2-4. Edits with vi commands

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