import { fn } from "https://deno.land/x/denops_lsputil@v0.9.4/deps.ts";
const { virtcol2col } = fn;
The result is a Number, which is the byte index of the character in window {winid} at buffer line {lnum} and virtual column {col}.
If buffer line {lnum} is an empty line, 0 is returned.
If {col} is greater than the last virtual column in line {lnum}, then the byte index of the character at the last virtual column is returned.
For a multi-byte character, the column number of the first byte in the character is returned.
The {winid} argument can be the window number or the
window-ID. If this is zero, then the current window is used.
Returns -1 if the window {winid} doesn't exist or the buffer line {lnum} or virtual column {col} is invalid.
See also screenpos(), virtcol() and col().
Can also be used as a method:
GetWinid()->virtcol2col(lnum, col)