### 2.5.1 Markup construction in Scheme

Markup expressions are internally represented in Scheme using the `markup` macro:

```(markup expr)
```

To see a markup expression in its Scheme form, use the `\displayScheme` command:

```\displayScheme
\markup {
\column {
\line { \bold \italic "hello" \raise #0.4 "world" }
\larger \line { foo bar baz }
}
}
```

Compiling the code above will send the following to the display console:

```(markup
#:line
(#:column
(#:line
(#:bold (#:italic "hello") #:raise 0.4 "world")
#:larger
(#:line
(#:simple "foo" #:simple "bar" #:simple "baz")))))
```

To prevent the markup from printing on the page, use ‘\void \displayScheme markup’. Also, as with the `\displayMusic` command, the output of `\displayScheme` can be saved to an external file. See Displaying music expressions.

This example demonstrates the main translation rules between regular LilyPond markup syntax and Scheme markup syntax. Using ```#{ … #}``` for entering in LilyPond syntax will often be most convenient, but we explain how to use the `markup` macro to get a Scheme-only solution.

 LilyPond Scheme `\markup markup1` `(markup markup1)` `\markup { markup1 markup2 … }` `(markup markup1 markup2 … )` `\markup-command` `#:markup-command` `\variable` `variable` `\center-column { … }` `#:center-column ( … )` `string` `"string"` `#scheme-arg` `scheme-arg`

The whole Scheme language is accessible inside the `markup` macro. For example, You may use function calls inside `markup` in order to manipulate character strings. This is useful when defining new markup commands (see New markup command definition).

#### Known issues and warnings

The markup-list argument of commands such as `#:line`, `#:center`, and `#:column` cannot be a variable or the result of a function call.

 ```(markup #:line (function-that-returns-markups)) ```

is invalid. One should use the `make-line-markup`, `make-center-markup`, or `make-column-markup` functions instead,

 ```(markup (make-line-markup (function-that-returns-markups))) ```

Other languages: deutsch, español, français.