Clear content in S:S when T:T contains "Copied" Google Script - google-apps-script

Question

I am stuck with, at first sight, simple script.
I want to clear a content from cell S when T has value "Copied".
What I have at the moment is this:
function onEdit(e) {
if(e.range.columnStart === 20) {
e.range.offset(0,-1).clearContent();
}
}
I am not sure how to include IF. Also, bear in mind that T column has a formula, so I don't edit it manually, and with this script, it doesn't work.
It doesn't have to be OnEdit, I can set a trigger to run the script every minute which is even better, but it is important to filter it by the value Copied.
To explain a bit more how my file works (example):
1) I add a comment in the cell S5.
2) My second script runs every minute where it copies values from column S to column V.
3) In the column T, I have the formula (=IF(V5<>"",IF(RegExMatch(S5,V5),"Copied",""),"")), which means if the value exist in the column V5 add Copied in cell T5.
4) I am looking for a solution that when cell T:T has "Copied", delete the cell range S:S
Thank you millions!

Answer 1

As #TheWizEd points out the value in T is dependant on the result in another cell. However an OnEdit function does not necessarily have to respond to the range where the change was made. I've used this code to use the OnEdit event to evaluate the values in Column T and then make the relevant change to values in Column S.
Column T uses a for loop to go through the various row, but the relevant value is pushed to array. This allows a single setValues to be executed at the end of the function.
The function should be assigned to the OnEdit trigger for the Spreadsheet.
function so_53469142() {
// Setup spreadsheet and target sheet
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheetByName("so_53469142");
// get the last row of data
var lastRow = sheet.getLastRow();
// get range for Column S & T
var values = sheet.getRange(1, 19, lastRow, 2).getValues();
// set counter variable
var i = 0;
var dataArray = [];
var masterArray = [];
// start loop
for (i = 0; i < lastRow; i++) {
// Logger.log("i="+i+", S = "+values[i][0]+", T = "+values[i][1]);//DEBUG
// empty the array
dataArray = [];
// test value of first row in T
if (values[i][1] === "Copied") {
// If value = "Copies then push blank onto array for Column S
dataArray.push("");
} else {
// else push existing value for column S
dataArray.push(values[i][0]);
}
// make the array 2D
masterArray.push(dataArray);
}
// Update values in Column S
sheet.getRange(1, 19, lastRow).setValues(masterArray);
}