E131: That type has no methods

A “method call” is thing.method(...). A struct can declare methods, so p.length() works on a Point that defines length. An int, a bool or a double has no methods of its own, so there is nothing for the dot to find:

mut x: int = 5;x.foo();                          // an int has no `foo`

Usually one of three things is going on:

• The name is misspelled, or it is a function in a module you meant to import. Many things are written module::function(x), not x.function(): math::abs(x).
• You called a method on the wrong variable.
• You meant a struct, and the variable’s type isn’t the struct you think it is.

An array has exactly two built-in methods, length() and copy(), and neither takes an argument. Anything else is this error too:

mut a: int[3] = [1, 2, 3];a.copy(1);                        // 'copy()' on an array takes no arguments, but was given 1.a.reverse();                      // Arrays have no method 'reverse'.mut s: string = "abc";s.copy();                         // Cannot call method 'copy' on type 'string' -- only struct instances have methods.

(copy() is for arrays only. To take part of an array, slice it first: a[1..3].copy().)

(x.f() does work on a non-struct when a function f taking that type is imported – that is how text.length() works on a string. So check the spelling, and that the module is imported.)

Run turf --explain E131 in a terminal to read this again.