Elm ultisnips

README.md

For use with https://github.com/SirVer/ultisnips

Case lambda

Multi-case

Record punning

Record constructor

Note:

The multi-case regex won't handle all patterns correctly. Things like Just 123 or Just "abc" etc. won't get picked up. Please tweak and share! 😇

elm.snippets

#####################################################
# Case lambda
# 
# \case
#
# -->
# 
# \x ->
#   case x of

snippet "\\case" "Case lambda" br
\\${1:x} ->
  case $1 of
    $2
endsnippet

#####################################################
# Multi-case
# 
# A, B -> 1
# 
# -->
# 
# A -> 1
# B -> 1

global !p
def gen_multicase(snip):
 line = snip.buffer[snip.line]

 indent = len(line) - len(line.lstrip())
 spaces = " " * indent

 cases_joined, result = [x.strip() for x in line.strip().split("->")]
 cases = [x.strip() for x in cases_joined.split(",")]

 snip.buffer[snip.line] = "" # erase the line

 case_lines = [f"{spaces}{case} -> {result}" for case in cases]
 line_content = "\n".join(case_lines)

 snip.expand_anon(line_content)
endglobal

post_jump "gen_multicase(snip)"
snippet "(([A-Za-z0-9]+, ?)+([A-Za-z0-9]+) ?->.*)" "Multi-case" br
`!p snip.rv = match.group(1)`
endsnippet

#####################################################
# Record punning
# 
# {a,b,c}
# 
# -->
# 
# { a = a, b = b, c = c }

global !p
def gen_recordpunning(snip):
 rec = match.group(1)
 inner = rec[1:-1]
 fields = [field.strip() for field in inner.split(",")]
 new_rec = "{ " + ", ".join([f"{field} = {field}" for field in fields]) + " }"

 snip.buffer[snip.line] = snip.buffer[snip.line][:-len(rec)]

 snip.expand_anon(new_rec)
endglobal

post_jump "gen_recordpunning(snip)"
snippet "(\{ *[a-z][a-zA-Z0-9_]*( *, *[a-z][a-zA-Z0-9_]*)* *\})" "Record punning" br
`!p snip.rv = match.group(1)`
endsnippet

#####################################################
# Record constructor
# 
# \->{a,b,c}
# 
# -->
# 
# \a b c -> { a = a, b = b, c = c }

global !p
def gen_recordconstructor(snip):
 match_str = match.group(1)
 inner = match_str[4:-1]
 fields = [field.strip() for field in inner.split(",")]
 field_names = " ".join(fields)
 new_str = "\\" + field_names + " -> { " + ", ".join([f"{field} = {field}" for field in fields]) + " }"

 snip.buffer[snip.line] = snip.buffer[snip.line][:-len(match_str)]

 snip.expand_anon(new_str)
endglobal

post_jump "gen_recordconstructor(snip)"
snippet "(\\->\{ *[a-z][a-zA-Z0-9_]*( *, *[a-z][a-zA-Z0-9_]*)* *\})" "Record constructor" br
`!p snip.rv = match.group(1)`
endsnippet