我很懒，使用优秀的EclipseFP IDE编写了一个Haskell模块，但没有为我的顶层函数提供类型签名。
EclipseFP使用HLint自动标记每个有问题的函数，我可以用4个鼠标点击来修复每一个。这很有效，但也很繁琐。
是否有一种实用程序可以扫描.hs文件，并生成一个修改后的版本，为每个顶层函数添加类型签名？
示例：
./addTypeSignatures Foo.hs
我想要读取一个名为Foo.hs的文件：
foo x = foo + a
并且触发
foo :: Num a => a -> a
foo x = x + 1
如果工具可以自动地直接在原地编辑Foo.hs并保存备份文件Foo.bak.hs，那就更好了。
对于emacs，有一个名为haskell-mode的工具，可以通过以下快捷键插入函数类型签名：C-u, C-c, C-t。它不是自动的，您需要为每个函数执行此操作。但如果您只有一个模块，可能只需要几分钟即可完成。
#!/usr/bin/env perl
use warnings;
use strict;
sub trim {
my $string = shift;
$string =~ s/^\s+|\s+$//g;
return $string;
}
my $sig=0;
my $file;
my %funcs_seen = ();
my %keywords = ();
for my $kw qw(type newtype data class) { $keywords{$kw} = 1;}
foreach $file (@ARGV)
{
if ($file =~ /\.lhs$/)
{
print STDERR "$file: .lhs is not supported. Skipping.\n";
next;
}
if ($file !~ /\.hs$/)
{
print STDERR "$file is not a .hs file. Skipping.\n";
next;
}
my $module = $file;
$module =~ s/\.hs$//;
my $browseInfo = `echo :browse | ghci $file`;
if ($browseInfo =~ /Failed, modules loaded:/)
{
print STDERR "$browseInfo\n";
print STDERR "$file is not valid Haskell source file. Skipping.\n";
next;
}
my @browseLines = split("\n", $browseInfo);
my $browseLine;
my $func = undef;
my %dict = ();
for $browseLine (@browseLines) {
chomp $browseLine;
if ($browseLine =~ /::/) {
my ($data, $type) = split ("::", $browseLine);
$func = trim($data);
$dict{$func} = $type;
print STDERR "$func :: $type\n";
} elsif ($func && $browseLine =~ /^ /) { # indent on continutation
$dict{$func} .= " " . trim($browseLine);
print STDERR "$func ... $browseLine\n";
} else {
$func = undef;
}
}
my $backup = "$file.bak";
my $new = "$module.New.hs";
-e $backup and die "Backup $backup file exists. Refusing to overwrite. Quitting";
open OLD, $file;
open NEW, ">$new";
print STDERR "Functions in $file:\n";
my $block_comment = 0;
while (<OLD>)
{
my $original_line = $_;
my $line = $_;
my $skip = 0;
$line =~ s/--.*//;
if ($line =~ /{-/) { $block_comment = 1;} # start block comment
$line =~ s/{-.*//;
if ($block_comment and $line =~ /-}/) { $block_comment=0; $skip=1} # end block comment
if ($line =~ /^ *$/) { $skip=1; } # comment/blank
if ($block_comment) { $skip = 1};
if (!$skip)
{
if (/^(('|\w)+)( +(('|\w)+))* *=/ )
{
my $object = $1;
if ((! $keywords{$object}) and !($funcs_seen{$object}))
{
$funcs_seen{$object} = 1;
print STDERR "$object\n";
my $type = $dict{$1};
unless ($sig)
{
if ($type) {
print NEW "$1 :: $type\n";
print STDERR "$1 :: $type\n";
} else {
print STDERR "no type for $1\n";
}
}
}
}
$sig = /^(('|\w)+) *::/;
}
print NEW $original_line;
}
close OLD;
close NEW;
my $ghciPostTest = `echo 1 | ghci $new`;
if ($ghciPostTest !~ /Ok, modules loaded: /)
{
print $ghciPostTest;
print STDERR "$new is not valid Haskell source file. Will not replace original (but you might find it useful)";
next;
} else {
rename ($file, $backup) or die "Could not make backup of $file -> $backup";
rename ($new, $file) or die "Could not make new file $new";
}
}
-Wmissing-signatures警告的hacky尝试，因此脚本不必解析Haskell。它将警告转换为sed脚本，并将其结果打印到stdout，或者如果给出-i，则就地修改文件。buildCmd。#!/bin/zsh
set -eu
setopt rematchpcre
help="Usage: ${0:t} [-d] [-i | -ii] HASKELL_FILE
Options:
-d Debug
-i Edit target file inplace instead of printing to stdout
(Warning: Trying to emulate this option by piping from
and to the same file probably won't work!)
-ii Like -i, but no backup
"
### CONFIG ###
buildCmd() {
touch $inputFile
stack build --force-dirty --ghc-options='-fno-diagnostics-show-caret -Wmissing-signatures'
}
# First group must be the filename, second group the line number
warningRegexL1='^(.*):([0-9]+):[0-9]+(-[0-9]+)?:.*-Wmissing-signatures'
# First group must be the possible same-line type signature (can be empty)
warningRegexL2='Top-level binding with no type signature:\s*(.*)'
# Assumption: The message is terminated by a blank line or an unindented line
messageEndRegex='^(\S|\s*$)'
### END OF CONFIG ###
zparseopts -D -E d=debug i+=inplace ii=inplaceNoBackup h=helpFlag
[[ -z $helpFlag ]] || { printf '%s' $help; exit 0 }
# Make -ii equivalent to -i -i
[[ -z $inplaceNoBackup ]] || inplace=(-i -i)
inputFile=${1:P} # :P takes the realpath
[[ -e $inputFile ]] || { echo "Input file does not exist: $inputFile" >&2; exit 2 }
topStderr=${${:-/dev/stderr}:P}
debugMessage()
{
[[ -z $debug ]] || printf '[DBG] %s\n' "$*" > $topStderr
}
debugMessage "inputFile = $inputFile"
makeSedScript()
{
local line
readline() {
IFS= read -r line || return 1
printf '[build] %s\n' $line >&2
}
while readline; do
[[ $line =~ $warningRegexL1 ]] || { debugMessage "^ Line doesn't match warningRegexL1"; continue }
file=${match[1]}
lineNumber=${match[2]}
[[ ${file:P} = $inputFile ]] || { debugMessage "^ Not our file: $file"; continue }
# Begin sed insert command
printf '%d i ' $lineNumber
readline
[[ $line =~ $warningRegexL2 ]] ||\
{ printf 'WARNING: Line after line matching warningRegexL1 did not match warningRegexL2:\n %s\n' $line >&2
continue }
inlineSig=${match[1]}
debugMessage "^ OK, inlineSig = $inlineSig"
printf '%s' $inlineSig
readline
if [[ ! ($line =~ $messageEndRegex) ]]; then
[[ $line =~ '^(\s*)(.*)$' ]]
indentation=${match[1]}
[[ -z $inlineSig ]] || printf '\\n'
printf ${match[2]}
while readline && [[ ! ($line =~ $messageEndRegex) ]]; do
printf '\\n%s' ${line#$indentation}
done
fi
debugMessage "^ OK, Type signature ended above this line"
# End sed insert command
printf '\n'
done
}
prepend() {
while IFS= read -r line; do printf '%s%s\n' $1 $line; done
}
sedScript="$(buildCmd |& makeSedScript)"
if [[ -z $sedScript ]]; then
echo "No type-signature warnings for the given input file were detected (try -d option to debug)" >&2
exit 1
fi
printf "\nWill apply the following sed script:\n" >&2
printf '%s\n' $sedScript | prepend "[sed] " >&2
sedOptions=()
if [[ $#inplace -ge 1 ]]; then
sedOptions+=(--in-place)
[[ $#inplace -ge 2 ]] || cp -p --backup=numbered $inputFile ${inputFile}.bak
fi
sed $sedOptions -f <(printf '%s\n' $sedScript) $inputFile
'ctrl-alt-T': 'haskell-ghc-mod:insert-type'
这个 Perl 脚本是一个粗糙的解决方案，对源文件结构做了一些假设。（例如：.hs 文件（而不是 .lhs），签名在定义的前一行，定义紧贴左边缘等）
它试图处理（跳过）注释、方程式样式的定义（带有重复的左侧），以及在 ghci 中生成多行输出的类型。
毫无疑问，许多有趣的有效情况没有得到妥善处理。该脚本远未尊重 Haskell 的实际语法。
它非常慢，因为它为每个需要签名的函数启动一个 ghci 会话。
它创建一个备份文件 File.hs.bak，将找到的函数和缺少签名的函数的签名打印到 stderr，并将升级后的源代码写入 File.hs。它使用一个中间文件 File.hs.new，并具有一些安全检查，以避免用垃圾覆盖您的内容。
请自行承担风险。
此脚本可能会格式化您的硬盘、烧毁您的房子、unsafePerformIO，并产生其他不纯的副作用。实际上，它很可能会这样做。
我感觉很肮脏。
在Mac OS X 10.6 Snow Leopard上进行了测试，使用了我的一些自己的.hs源文件。
#!/usr/bin/env perl
use warnings;
use strict;
my $sig=0;
my $file;
my %funcs_seen = ();
my %keywords = ();
for my $kw qw(type newtype data class) { $keywords{$kw} = 1;}
foreach $file (@ARGV)
{
if ($file =~ /\.lhs$/)
{
print STDERR "$file: .lhs is not supported. Skipping.";
next;
}
if ($file !~ /\.hs$/)
{
print STDERR "$file is not a .hs file. Skipping.";
next;
}
my $ghciPreTest = `echo 1 | ghci $file`;
if ($ghciPreTest !~ /Ok, modules loaded: /)
{
print STDERR $ghciPreTest;
print STDERR "$file is not valid Haskell source file. Skipping.";
next;
}
my $module = $file;
$module =~ s/\.hs$//;
my $backup = "$file.bak";
my $new = "$module.New.hs";
-e $backup and die "Backup $backup file exists. Refusing to overwrite. Quitting";
open OLD, $file;
open NEW, ">$new";
print STDERR "Functions in $file:\n";
my $block_comment = 0;
while (<OLD>)
{
my $original_line = $_;
my $line = $_;
my $skip = 0;
$line =~ s/--.*//;
if ($line =~ /{-/) { $block_comment = 1;} # start block comment
$line =~ s/{-.*//;
if ($block_comment and $line =~ /-}/) { $block_comment=0; $skip=1} # end block comment
if ($line =~ /^ *$/) { $skip=1; } # comment/blank
if ($block_comment) { $skip = 1};
if (!$skip)
{
if (/^(('|\w)+)( +(('|\w)+))* *=/ )
{
my $object = $1;
if ((! $keywords{$object}) and !($funcs_seen{$object}))
{
$funcs_seen{$object} = 1;
print STDERR "$object\n";
my $dec=`echo ":t $1" | ghci $file | grep -A100 "^[^>]*$module>" | grep -v "Leaving GHCi\." | sed -e "s/^[^>]*$module> //"`;
unless ($sig)
{
print NEW $dec;
print STDERR $dec;
}
}
}
$sig = /^(('|\w)+) *::/;
}
print NEW $original_line;
}
close OLD;
close NEW;
my $ghciPostTest = `echo 1 | ghci $new`;
if ($ghciPostTest !~ /Ok, modules loaded: /)
{
print $ghciPostTest;
print STDERR "$new is not valid Haskell source file. Will not replace original (but you might find it useful)";
next;
} else {
rename ($file, $backup) or die "Could not make backup of $file -> $backup";
rename ($new, $file) or die "Could not make new file $new";
}
}
:browse，就能使它运行得更快。 - ehird
hs-lint-replace-without-ask设置为t，Emacs中的hs-lint命令将自动应用建议。我不确定如何将其限制为仅适用于类型签名，但肯定有一种方法。我之所以只是发布评论，是因为这不是EclipseFP解决方案。 - Jon Purdy