Can't recursively concat

Is this the expected behaviour for liquid, to not be able to assign recursively?

{% assign yes = "yes" | split: "," %}
    <h5>Does concat work?</h5>
    {% assign yes = yes | concat: yes %}
    {{ yes }}

Prints out [“yes”], as opposed to [“yes”, “yes”]

[harttle]

It’s because not implemented. Now it’s available in 2.0.0 by this commit.

Note: 2.0.0 may not be backward-compatible with 1.x, mainly in whitespace control options.

[rjbergerud]

Thanks!