m4 - 需要 m4 宏将边距添加到任意文本

Question

假设我定义了一个 m4 宏 FOOBAR，其中包含一段任意文本，其中可能包含逗号字符。请创建一个 m4 宏以将 5 个空格的左边距添加到 FOOBAR 文本的扩展中。

如果文本不包含任何逗号，问题很简单（只需使用带有“^”正则表达式的 patsubst）。但我需要处理逗号。

谢谢！

Answer 1

需要打磨，但这是一个开始：

m4_divert(-1)

I changed the m4 quoting to use [<{}>]

m4_define(_spaces,[<{m4_format([<{%}>]$1[<{s}>],)}>])

m4_define(_indent,[<{m4_patsubst($1,[<{^}>],_spaces($2))}>])

m4_define(_Comma_and_Paren_Safe,[<{m4_patsubst([<{[<{Some. arbitrary text,with unbalanced parentheses like:
((()((((
and several commas ,,,, and a few, more , of those 
commas,,.
}>]}>],[<{,}>],[<{[<{,}>]}>])}>])


m4_divert(0)m4_dnl
_indent([<{_Comma_and_Paren_Safe}>],7)

示例运行（_m42 是简单的 m4 包装脚本）：

$ _m42 < ~/tmp/2v.STDIN.m4-margin.SatMay16.2052.190
       Some. arbitrary text,with unbalanced parentheses like:
       ((()((((
       and several commas ,,,, and a few, more , of those 
       commas,,.

Answer 2

比以前的尝试更简单：保存到宏 FOOBAR - 嵌套在四引号内的任意文本段落以保护逗号和不平衡的括号：

m4_divert(-1)

m4_define(_spaces,[<{m4_format([<{%}>]$1[<{s}>],)}>])

m4_define(_indent,[<{m4_patsubst($1,[<{^}>],_spaces($2))}>])

--
Simpler than prior attempt: save arbitrary text paragraph nested inside
quadruple quote to protect commas, and unbalanced parentheses:

m4_define(FOOBAR,[<{[<{[<{[<{Some. arbitrary text,with unbalanced parentheses like:
((()((((
and several commas ,,,, and a few, more , of those
commas,,.
}>]}>] }>]}>])

m4_divert(0)m4_dnl
_indent(FOOBAR,15)

示例运行：

$ _m42 < ~/tmp/2v.STDIN.m4-margin.SatMay16.2052.190
               Some. arbitrary text,with unbalanced parentheses like:
               ((()((((
               and several commas ,,,, and a few, more , of those
               commas,,.