Inner-object possibilities

Question

What are the possible uses of the inner-something command in vim? For example, the following three items work:

• ci) in ("hello")
• ci' in 'hello'
• ci] in ([var])

But the following two do not:

• ci# in # TODO #
• ci" in:

"""
This is a python docstring.
"""

What are the various limitations then or possibilities in using the i (as in "inner") command?

Answer 1

All of the text-objects are documented under :help text-objects.

Excerpted from :help objects:

|v_iquote|  i"         double quoted string without the quotes
|v_i'|      i'         single quoted string without the quotes
|v_i(|      i(         same as ib
|v_i)|      i)         same as ib
|v_i<|      i<         "inner <>" from '<' to the matching '>'
|v_i>|      i>         same as i<
|v_iB|      iB         "inner Block" from "[{" and "]}"
|v_iW|      iW         "inner WORD"
|v_i[|      i[         "inner []" from '[' to the matching ']'
|v_i]|      i]         same as i[
|v_i`|      i`         string in backticks without the backticks
|v_ib|      ib         "inner block" from "[(" to "])"
|v_ip|      ip         "inner paragraph"
|v_is|      is         "inner sentence"
|v_it|      it         "inner tag block"
|v_iw|      iw         "inner word"
|v_i{|      i{         same as iB
|v_i}|      i}         same as iB