Typo

[matthieugomez]

I often write

for i in length(x)

when really I want to write

for i in 1:length(x)

This typo is surprisingly easy to do and hard to spot. Would it be possible to return a warning or an error in the first case?

[ScottPJones]

Does Lint.jl catch that?

[yuyichao]

See #11769

[jakebolewski]

Unfortunately no, numbers are iterable so for i=length(x) is perfectly valid. Lint.jl can't catch it because all Lint can do is look at the AST, and it can't infer the type that length will return.

[Ken-B]

For your information, the NEWS section for v0.4 says "Array iteration should generally be written as for i in eachindex(A) ... end rather than for i = 1:length(A) ... end. (#8432)"

I would think this will fix your typo issue.