How to make Helm always add ^ to the input pattern

Question

Is there a way in Helm to first match substrings from the beginning and only after that in the middle of candidates?

For instance, I have the following directory structure:

~/
    .emacs.d/
    .gem/
    .microemulator/

And I want to open a file in the directory .emacs.d. I start to type .em and Helm matches .gem first.

How to make Helm match .emacs.d first, without prepending the beginning of line symbol (^)?

Answer 1

It's possible with a pattern-transformer. Here's a sample code:

(helm :sources
          `((name . "Headings")
            (candidates . ,candidates)
            (action . (lambda (x) (goto-char x)
                         (call-interactively 'show-branches)
                         (worf-more)))
            (pattern-transformer . worf--pattern-transformer)))

(defun worf--pattern-transformer (x)
  "Transform X to make 1-9 select the heading level in `worf-goto'."
  (if (string-match "^[1-9]" x)
      (setq x (format "^%s" x))
    x))

Answer 2

The reason the character is not included because potentially a filename can contain that character. Btw, you are using the Helm version of find-file, not the actual helm-find-files. The helm-find-files command can fuzzy match, so you can just type "emd" to get to ~/.emacs.d, and even if you type "em", the command should give you ~/.emacs.d first. Check the helm-find-files section in my guide.