Vim syntax highlighting for amrex input files

amrex.vim

" Vim syntax file
" Language:               Input file for AMReX codes, based on "dosini" syntax v2.1
" Version:                2.1
" Homepage:
" Last Change:            2022 June 22


" For version 5.x: Clear all syntax items
" For version 6.x: Quit when a syntax file was already loaded
if version < 600
  syntax clear
elseif exists("b:current_syntax")
  finish
endif

" shut case off
syn case ignore

syn match  dosiniNumber   "\<\d\+\>"
syn match  dosiniNumber   "\<\d*\.\d\+\>"
syn match  dosiniNumber   "\<\d\+e[+-]\=\d\+\>"
syn match  dosiniLabel    "^.\{-}="
syn region dosiniHeader   start="^\s*\[" end="\]"
syn match  dosiniComment  "^[#;].*$"

" Additional tweaks for numerical values
" see: https://vim.fandom.com/wiki/Creating_your_own_syntax_files#Matches_(and_addendum_to_keywords)
" - Integer with - + or nothing in front
syn match dosiniNumber '\d\+'
syn match dosiniNumber '[-+]\d\+'
" - Floating point number with decimal no E or e
syn match dosiniNumber '[-+]\d\+\.\d*'
" - Floating point like number with E and no decimal point (+,-)
syn match dosiniNumber '[-+]\=\d[[:digit:]]*[eE][\-+]\=\d\+'
syn match dosiniNumber '\d[[:digit:]]*[eE][\-+]\=\d\+'
" - Floating point like number with E and decimal point (+,-)
syn match dosiniNumber '[-+]\=\d[[:digit:]]*\.\d*[eE][\-+]\=\d\+'
syn match dosiniNumber '\d[[:digit:]]*\.\d*[eE][\-+]\=\d\+'

" Define the default highlighting.
" For version 5.7 and earlier: only when not done already
" For version 5.8 and later: only when an item doesn't have highlighting yet
if version >= 508 || !exists("did_dosini_syntax_inits")
  if version < 508
    let did_dosini_syntax_inits = 1
    command -nargs=+ HiLink hi link <args>
  else
    command -nargs=+ HiLink hi def link <args>
  endif

  HiLink dosiniNumber   Number
  HiLink dosiniHeader   Special
  HiLink dosiniComment  Comment
  HiLink dosiniLabel    Type

  delcommand HiLink
endif

let b:current_syntax = "dosini"

" vim: sts=2 sw=2 et