How can I create a decorative bar by repeating an image?

[Olaf]

I would like to display a decorative bar in the header of my document. I have a small image that I want to render multiple times next to each other to create a horizontal image bar. I know that Typst has a For loop, but I don’t realise how to apply this to my problem. When do I know when I can stop because the right edge has been reached?

[Mathemensch]

I guess the pattern function could help you.
I had a very similar question:

How to use a pattern image as the page background?

I am currently creating some worksheets for exciting, context-orientated lessons. I have an image that I would like to use as the background for these documents. The image is a seamless pattern, so I would like to repeat it in the background instead of stretching it across the entire width. Is there a good way to repeat a background like a cache? So far I am stretching the background to the full height and width of the document. However, as the document gets longer, the quality gets worse and …

[sijo]

This sounds like a job for the repeat function

[Olaf]

The hint to the pattern function helped me:

#let tile = image(
  "./images/ornament.png",
  height: 8mm
)

#let tile_pattern = pattern(tile)

#rect(
  width: 100%, 
  height: 8mm,
  fill: tile_pattern
)

[Olaf]

The pattern function caused difficulties. The tile was repeated correctly in the header. Unfortunately, this only worked on every second page in the footer. The title was shifted on the faulty pages. After a lot of trial and error, I was able to find a solution based on the repeat function:

#let ornament = repeat(
  justify: false,
  image("./images/ornament.png", height: 15mm),
)

#set page(
  flipped: true,
  margin: (top: 21mm, bottom: 21mm, left: 5mm, right: 5mm),
  header: align(top, pad(x: -10mm, top: 2mm, ornament)),
  footer: align(bottom, pad(x: -10mm, bottom: 2mm, ornament)),
)