Backslash in trigger

[gzagatti]

It seems like backlash in the trigger function does not work. I have the following rule:

{
  "begin": {
    "prefix": ["\\begin"],
    "body": [
      "\\begin{$1}",
      "$0",
      "\\end{$1}"
    ],
    "description": "environment template."
  }
}

However, the completion does not get triggered. If I modify to "prefix": ["begin"] then the completion works.

I am using cmp to manage auto-completion.