Question

在bash gettng中，用大写字母替换的东西非常简单：

echo to_camel_case__variable | sed -r 's/(.)_+(.)/\1\U\2/g;s/^[a-z]/\U&/'

但是如果我不想更换怎么办？如果我只是想制作可变的pascal大小写而又保留下划线怎么办？

Answer 1

这有效：

echo 'this_is_a_test' | sed 's/[^_]\+/\L\u&/g'

我会测试一下，但看起来很可靠。

Answer 2

作为不依赖外部工具的纯bash实现（尽管需要现代bash 4.x）：

case $BASH_VERSION in ''|[123].*) echo "ERROR: Bash 4.x+ required" >&2; exit 1;; esac

to_pascal_with_underscores() {
  local s=${1^} re='(.*_+)([[:lower:]].*)'    # initially capitalize 1st char
  while [[ $s =~ $re ]]; do                   # match string $s against regex $re
    s=${BASH_REMATCH[1]}${BASH_REMATCH[2]^}   # capitalize first character of 2nd group
  done
  printf '%s\n' "$s"                          # avoid unreliable behavior associated w/ echo
}

to_pascal_with_underscores this_is_a_test
to_pascal_with_underscores to_camel_case__variable

...正确发射This_Is_A_Test和To_Camel_Case__Variable，如https://ideone.com/yen0T2

所示

Bash变量为骆驼案/帕斯卡案

2 个答案: