用于 bash 补全的“have”关键字

Is havebash 中的关键字？或者 bash 补全脚本使用非 bash 的语言吗？

have gcc &&
_gcc()
{

是很常见。看：grep "have .* &&" /etc/bash_completion.d/*

我找不到有关我见过的 bash 完成教程的任何信息，也找不到任何信息man bash。谷歌搜索“有”也很困难。我在哪里可以找到这方面的文档？

我猜这与确保存在有关gcc存在于PATH?

编辑：是的。/etc/bash_completion包含：

have()
{
    unset -v have
    # Completions for system administrator commands are installed as well in
    # case completion is attempted via `sudo command ...'.
    PATH=$PATH:/sbin:/usr/sbin:/usr/local/sbin type $1 &>/dev/null &&
    have="yes"
}

have and _have只是在基础中定义的两个函数bash_completion文件。在两者之间，它们形成了内置的包装器type命令来确定特定命令/程序是否可用。

# This function checks whether we have a given program on the system.
#
_have()
{
    # Completions for system administrator commands are installed as well in
    # case completion is attempted via `sudo command ...'.
    PATH=$PATH:/usr/sbin:/sbin:/usr/local/sbin type $1 &>/dev/null
}

# Backwards compatibility for compat completions that use have().
# @deprecated should no longer be used; generally not needed with dynamically
#             loaded completions, and _have is suitable for runtime use.
have()
{
    unset -v have
    _have $1 && have=yes
}