Less uses the method passed in from the previous layer to report an error

<style type="text/less">
    @b:b;
    .test{
        .a(@x:200px){
            width: @x;
            .b(@y:400px){
                width: @x;
            }
        }
    }
    -sharp@{b}{
        .test > .a > .b(200px);
    }
</style>
<script src="//cdnjs.cloudflare.com/ajax/libs/less.js/2.7.2/less.min.js"></script>


<div class="test"></div>
<div id="b">
    <span></span>
    <span class="test">1111111111</span>
</div>

Why do you read the materials on @ x undefined and say that you can use the method passed in from the upper level, that is, @ x

in .b?
Mar.31,2021
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b3e8ca-2c436.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b3e8ca-2c436.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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