isAdjacentFile function
function to check if character is adjacent to another character
Implementation
bool isAdjacentFile(String columnName, String isAdjacent) {
return (columnName.contains(
String.fromCharCode((isAdjacent[0][0]).codeUnitAt(0) - 1)) ||
columnName
.contains(String.fromCharCode((isAdjacent[0][0]).codeUnitAt(0) + 1)));
}