The Demystification of Singlish exclamation(By a Malaysian :p)
-har ~ to show uncertainty in what you have just said [eg. wat u mean, har]
-hor ~ to stress what you have just said [eg. u betta eat this, hor]
-loh ~ to show that you don't care and tints of slight frustration [eg. I dun understand wat u mean, lor]
-leh ~ to lightly plead or manja [eg. dun lyk dis, leh]
-lah ~ to show some extent of carefree-ness [eg. verry farnie, lah]
And to achieve a greater comical effect, please stop for one second before you say the Singlish exclamation. Therefore the comma is used in the examples.
Another piece of goodie brought to you proudly by the GOAT