Introduction

Suppose that we have the following text in normal mode (cursor is indicated by ^):

hello world
^

If we use dw, we delete hello<Space>1 and only world is left; if we use de, hello is deleted and <Space>world is left. Have you ever wondered about why dw do not delete w while de will delete the o in hello? It seems that motion e and w are somewhat inconsistent in their behaviours. It turns out that it has something to do with the exclusivity of motions in Vim.

Exclusive and inclusive motion explained

Most Vim motions are either exclusive or inclusive. This nature of a motion is best revealed when you perform an operation (these operations include, but are not limited to c, d, y) followed by these motions. Inclusive means that the texts between the start and end position of the cursor is used for that operation, while exclusive means that the last character near the end of current buffer2 is not included in the operation.

If you had known the above difference between the exclusive and inclusive motion, you would not be surprised about the so called inconsistency between dw and de. The reason is that w is an exclusive motion and e is an inclusive motion. Someone has asked on the Stack Exchange site on why backward delete such db can not delete the character in the cursor position. That is also because b is an exclusive motion so that the last character toward the end of the buffer is not included.

Change the exclusivity of a motion

To force an exclusive motion to be inclusive or vice versa, you can prepend the motion by v (from Vim doc):

v       When used after an operator, before the motion command: Force
        the operator to work characterwise, also when the motion is
        linewise.  If the motion was linewise, it will become
        |exclusive|.
        If the motion already was characterwise, toggle
        inclusive/exclusive.  This can be used to make an exclusive
        motion inclusive and an inclusive motion exclusive.

Take the case in the first paragraph for an example, dvw will delete hello<Space>w (w becomes inclusive) and dve will delete only hell (e becomes exclusive). To find more detailed doc on this behaviour, read :h exclusive carefully.

References


  1. <Space> indicates a space character. ↩︎

  2. You need to interpret this carefully. When you do forward motions, the last character is where the motion lands. If you do backward motions, the last character in this context means the character your motion starts at. ↩︎