Adding indentation after setting \setlength\parindent{0pt}'

Question

I am looking for a way to add an indentation after setting \parindent to 0. I tried a suitable amount of search, but none really seemed to meet my needs.

I tried to change the command \indent by inserting spaces:

\renewcommand{\indent}{\hspace{15pt}}

However, \indent did not add any extra space at the start of a new paragraph.

Can anyone please help me?

Answer 1

First store the original indent by adding

\newlength{\saveparindent}
\AtBeginDocument{\setlength}{\saveparindent}{\parindent}}

to your preamble. Then also add

\newcommand{\indentpar}{\par\hspace*{\saveparindent}\ignorespaces}

as your new indentation mechanism.

Assuming you have \setlength{\parindent}{0pt} somewhere else in your document you should now be able to use it in the following way:

\documentclass{article}

\newlength{\saveparindent}
\AtBeginDocument{\setlength{\saveparindent}{\parindent}}
\newcommand{\indentpar}{\par\hspace*{\saveparindent}\ignorespaces}

\begin{document}

This is an indented paragraph.

\setlength{\parindent}{0pt}% Remove paragraph indentation
This is a paragraph that is not indented.

\indentpar
Here is a new indented paragraph.

\end{document}

Of course, LaTeX also provides \noindent, if you're only interested in some non-indented paragraphs:

\documentclass{article}

\begin{document}

This is an indented paragraph.

\noindent% Remove paragraph indentation just for this paragraph
This is a paragraph that is not indented.

Here is a new indented paragraph.

\end{document}

Answer 2

You should always be able to use \hspace for this purpose: \hspace{5mm}

EDIT:
In order for \hspace to work you probably have to switch from vertical to horizontal mode using \leavevmode. See Function and usage of \leavevmode and What are vertical and horizontal modes?

So all in all this should work: \leavevmode\hspace{5mm}