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Mojo trait

Writable

The Writable trait describes how a type is written into a Writer.

You must implement write_to which takes self and a type conforming to Writer:

struct Point(Writable):
    var x: Float64
    var y: Float64

    fn write_to[W: Writer](self, inout writer: W):
        var string = "Point"
        # Write a single `Span[Byte]`:
        writer.write_bytes(string.as_bytes())
        # Pass multiple args that can be converted to a `Span[Byte]`:
        writer.write("(", self.x, ", ", self.y, ")")
struct Point(Writable):
    var x: Float64
    var y: Float64

    fn write_to[W: Writer](self, inout writer: W):
        var string = "Point"
        # Write a single `Span[Byte]`:
        writer.write_bytes(string.as_bytes())
        # Pass multiple args that can be converted to a `Span[Byte]`:
        writer.write("(", self.x, ", ", self.y, ")")

Implemented traits​

AnyType

Methods​

write_to​

write_to[W: Writer](self: _Self, inout writer: W)

Formats the string representation of this type to the provided Writer.

Parameters:

  • ​W (Writer): A type conforming to the Writable trait.

Args:

  • ​writer (W): The type conforming to Writable.