What's the recommended way to make a snippet fire only inside an environment?

[medwatt]

The snippet below creates a snippet for the if statement. Suppose I would like to bind the keys @@ to create an elseif block under the condition that @@ only does this when I'm inside an if statement. How can I do that?

s(
    { trig = "if", dscr = "if statement" },
    fmta(
        [[
            if <> then
                <>
            end
        ]],
        {
            i(1, "condition"),

            c(2,
                {
                    i(1),
                    sn(2, { i(1), t({"","else", "\t"}), i(2) }),
                    sn(3, { i(1), t({"","elseif "}), i(2, "condition"), t({" then", "\t"}), i(3), t({"","else", "\t"}), i(4) }),
                }
            )
        }
    ),
)

[L3MON4D3]

Check out :h luasnip-snippets and look for condition, it makes it possible to disallow expansion if some condition (cursor in an if-statement) does not hold

[medwatt]

Thanks for the reply. There's a lot of condition match. So, I don't know which part you're referring to.

As an additional question, how does the snippet know when the cursor is inside an if statement?

[L3MON4D3]

There's a lot of condition match. So, I don't know which part you're referring to.

I can't link to the exact line , unfortunately, but there's a list of valid keys for the first argument to snippet/s, it's in there (search for "but we already have that info here", that should be unique)

As an additional question, how does the snippet know when the cursor is inside an if statement?

Ah, that's for you to figure out 😅
treesitter is pretty good at stuff like this, but if you're not familiar with that it might take a bit to get it working.. just searching the buffer is also an option, but more prone to errors.