Today, when I edited the LaTeX document for my personal project, the cdlatex expansion took precedence over the YASnippet expansion, which made the latter not function properly. Such a phenomenon has not appeared before.

Solution

  1. Create the following Elisp function tjh/cdlatex-yas-expand, in which the YASnippet expansion will be tried first. If successful, this function returns t and the default cdlatex expansion will be ignored. Otherwise, the cdlatex expansion will be used.

    (defun tjh/cdlatex-yas-expand ()
  "Resolve the conflict between cdlatex and yasnippet. When this
function returns true, the default `cdlatex-tab` will not be
executed. The effect of function is to first try yasnippet
expansion, then cdlatex expansion."
  (interactive)
  (if (or (bound-and-true-p yas-minor-mode)
          (bound-and-true-p yas-global-mode))
      (if (yas-expand)
          t
        nil)
    nil))

  2. Add tjh/cdlatex-yas-expand to cdlatex-tab-hook.

    (add-hook 'cdlatex-tab-hook 'tjh/cdlatex-yas-expand)