Bazel中没有直接支持嵌套select的方法，但是可以通过使用“$(function …)”语法来模仿它。下面是一个示例：

load("@bazel_tools//tools/build_defs/selects:selects.bzl", "select")
def my_rule(name):
    select({
        "//conditions:default": [
            # Actions for the default conditiongo here
            # Note the use of $() to do nested selects
            "\$(function() { return select({\n"
            "    \"//conditions:a\": [\n"
            "        # Actions for condition a\n"
            "    ],\n"
            "    \"//conditions:b\": [\n"
            "        # Actions for condition b, which requires\n"
            "        # first selecting from a set of options\n"
            "        \"\$(function() { return select({\n"
            "            \"//options:1\": [\n"
            "                # Actions for option 1\n"
            "            ],\n"
            "            \"//options:2\": [\n"
            "                # Actions for option 2\n"
            "            ],\n"
            "        }, default = \"//options:1\")() });\")\n"
            "    ],\n"
            "}, default = \"//conditions:a\")() });\n"
        ],
        "//conditions:a": [  # Actions for condition a
        ],
        "//conditions:b": [  # Actions for condition b
        ],
    }, name = name)

在此示例中，有一个名为“my_rule”的规则，其中包含条件为“//conditions:default”、“//conditions:a”和“//conditions:b”。为了模仿嵌套选择，将“$(function () {…}）”用于嵌套选择。在条件“//conditions:b”中，需要先选择一组选项，然后根据所选选项执行相关操作。这个选择过程也使用了嵌套选择。

虽然这种解决方法可能会使代码变得更加复杂，但是它提供了一种方式来在Bazel构建中实现嵌套选择。