🌲 #newfeature
Compiler warnings
Warning messages are now issued in certain circumstances when you add a script to a chart. This is one example, for cases where you initialize a new instance of a global variable in a local scope with = instead of assigning the global scope variable a new value using :=. We called those "silent killers" because they were rarely intentional, yet sometimes difficult to spot when debugging code.

Here is an example of code that will generate a warning when you add it to a chart:

//@version=4
study("")
a = 1
if close > open
    a = 2
plot(a)

In this case, variable a will never plot with a value of 2 because it is initialized in the if statement's local scope and disappears from view when the block ends. The coder's intention would have required, instead:

//@version=4
study("")
a = 1
if close > open
    a := 2
plot(a)