Add Python lexer.HEADmaster

1 files changed, 94 insertions, 0 deletions

diff --git a/syntax-highlight/python.scm b/syntax-highlight/python.scm
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+;;; guile-syntax-highlight --- General-purpose syntax highlighter
+;;; Copyright © 2023 Skylar Chan <schan12@terpmail.umd.edu>
+;;;
+;;; Guile-syntax-highlight is free software; you can redistribute it
+;;; and/or modify it under the terms of the GNU Lesser General Public
+;;; License as published by the Free Software Foundation; either
+;;; version 3 of the License, or (at your option) any later version.
+;;;
+;;; Guile-syntax-highlight is distributed in the hope that it will be
+;;; useful, but WITHOUT ANY WARRANTY; without even the implied
+;;; warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+;;; See the GNU Lesser General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU Lesser General Public
+;;; License along with guile-syntax-highlight.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+;;
+;; Syntax highlighting for Python.
+;;
+;;; Code:
+
+(define-module (syntax-highlight python)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:use-module (syntax-highlight lexers)
+  #:export (lex-python))
+
+(define %python-reserved-words
+  '("False"   "await"     "else"     "import"    "pass"
+    "None"    "break"     "except"   "in"        "raise"
+    "True"    "class"     "finally"  "is"        "return"
+    "and"     "continue"  "for"      "lambda"    "try"
+    "as"      "def"       "from"     "nonlocal"  "while"
+    "assert"  "del"       "global"   "not"       "with"
+    "async"   "elif"      "if"       "or"        "yield"))
+
+(define (python-reserved-word? str)
+  "Return #t if STR is a python keyword."
+  (any (cut string=? <> str) %python-reserved-words))
+
+(define %python-builtin-functions
+  '("abs"          "delattr"    "hash"        "memoryview"  "set"
+    "all"          "dict"       "help"        "min"         "setattr"
+    "any"          "dir"        "hex"         "next"        "slice"
+    "ascii"        "divmod"     "id"          "object"      "sorted"
+    "bin"          "enumerate"  "input"       "oct"         "staticmethod"
+    "bool"         "eval"       "int"         "open"        "str"
+    "breakpoint"   "exec"       "isinstance"  "ord"         "sum"
+    "bytearray"    "filter"     "issubclass"  "pow"         "super"
+    "bytes"        "float"      "iter"        "print"       "tuple"
+    "callable"     "format"     "len"         "property"    "type"
+    "chr"          "frozenset"  "list"        "range"       "vars"
+    "classmethod"  "getattr"    "locals"      "repr"        "zip"
+    "compile"      "globals"    "map"         "reversed"    "__import__"
+    "complex"      "hasattr"    "max"         "round"))
+
+(define (python-builtin-function? str)
+  "Return #t if STR is a python built-in function."
+  (any (cut string=? <> str) %python-builtin-functions))
+
+(define %python-operators
+  '("+"   "-"   "*"   "**"   "/"    "//"  "%"  "@"
+    "<<"  ">>"  "&"   "|"    "^"    "~"   ":="
+    "<"   ">"   "<="  ">="   "=="   "!="
+    ;;  delimiters
+    ","   ":"   "."   ";"    "@"    "="   "->"
+    "+="  "-="  "*="  "/="   "//="  "%="  "@="
+    "&="  "|="  "^="  ">>="  "<<="  "**="))
+
+(define lex-python-operator
+  (lex-any* (map lex-string %python-operators)))
+
+(define char-set:python-identifier
+  (char-set-adjoin char-set:letter+digit #\_))
+
+(define lex-python-identifier
+  (lex-char-set char-set:python-identifier))
+
+(define lex-python
+  (lex-consume
+   (lex-any (lex-char-set char-set:whitespace)
+            (lex-tag 'open (lex-any* (map lex-string '("(" "[" "{"))))
+            (lex-tag 'close (lex-any* (map lex-string '(")" "]" "}"))))
+            (lex-tag 'comment (lex-any (lex-delimited "#" #:until "\n")
+                                       (lex-delimited "\"\"\"" #:until "\"\"\"")
+                                       (lex-delimited "'''" #:until "'''")))
+            (lex-tag 'special (lex-filter python-reserved-word? lex-python-identifier))
+            (lex-tag 'operator lex-python-operator)
+            (lex-tag 'keyword (lex-filter python-builtin-function? lex-python-identifier))
+            (lex-tag 'symbol lex-python-identifier)
+            (lex-tag 'string (lex-any (lex-delimited "\"")
+                                      (lex-delimited "'"))))))