[TOT] Set city coastal flag in game?

[ThisIsAnotherBob]

Hello,
I am wondering if anyone has done any work to be able to change a city's coastal flag in game? I am aware that save editors can change this flag, but I was hoping to be able to set the flag during a game. ToTPP Lua has the ability to 'get' the coastal flag for a city but not to set the flag. My rough idea is to create a function to change a land square to an ocean square, check all adjacent squares to the changed square for cities, and if the coastal flag is false for an adjacent city then be able to change the city to a coastal city so that it can build ships and improvements.
Is there a way to directly set the coastal flag or some kind of workaround that anyone has found?

 

[Prof. Garfield]

The General Library of my Lua Scenario Template has functions to change that. Unless I made a mistake at some point, generalLibrary.lua can be used independently of the larger template (though a few functions won't work).

gen.setBuildCoastal
gen.clearBuildCoastal
gen.setBuildShips
gen.clearBuildShips

These functions use the city.attributes field. I don't know which of these city.coastal is checking.