Hide keyboard shortcuts

Hot-keys on this page

r m x p   toggle line displays

j k   next/prev highlighted chunk

0   (zero) top of page

1   (one) first highlighted chunk

1# -*- coding: utf-8 -*- 

2""" 

3@file 

4@brief Magic command to handle files 

5""" 

6from __future__ import print_function 

7import warnings 

8with warnings.catch_warnings(): 

9 warnings.simplefilter("ignore") 

10 from IPython.core.magic import Magics, magics_class 

11 

12 

13@magics_class 

14class MagicClassWithHelpers(Magics): 

15 

16 """ 

17 Provides some functions reused in others classes inherited from *Magics*. 

18 The class should not be registered as it is but should be 

19 used as an ancestor for another class. 

20 It can be registered this way:: 

21 

22 def register_file_magics(): 

23 from IPython import get_ipython 

24 ip = get_ipython() 

25 ip.register_magics(MagicFile) 

26 """ 

27 

28 _parser_store = {} 

29 

30 @property 

31 def Context(self): 

32 """ 

33 return the context or None 

34 """ 

35 if self.shell is None: 

36 return None 

37 return self.shell.user_ns 

38 

39 def add_context(self, context): 

40 """ 

41 add context to the class, mostly for debug purpose 

42 

43 @param context dictionary 

44 """ 

45 if self.shell is None: 

46 class EmptyClass: 

47 

48 def __init__(self): 

49 self.user_ns = {} 

50 self.shell = EmptyClass() 

51 for k, v in context.items(): 

52 self.shell.user_ns[k] = v 

53 

54 def get_parser(self, parser_class, name): 

55 """ 

56 Returns a parser for a magic command, initializes it 

57 if it does not exists, it creates it. The parsers are stored 

58 in static member *_parser_store*. 

59 

60 @param parser_class the parser to use for this magic command 

61 @param name name of the static variable which will contain the parser 

62 

63 See method @see me get_args 

64 """ 

65 res = MagicClassWithHelpers._parser_store.get(name, None) 

66 if res is None: 

67 MagicClassWithHelpers._parser_store[name] = parser_class() 

68 return MagicClassWithHelpers._parser_store[name] 

69 return res 

70 

71 def get_args(self, line, parser, print_function=print): 

72 """ 

73 parser a command line with a given parser 

74 

75 @param line string (command line) 

76 @param parser parser which has to be used to parse *line* 

77 @param print_function function to use to display the help 

78 @return results 

79 

80 If the line cannot be parsed, the function displays the help 

81 using function print. 

82 

83 Example:: 

84 

85 @line_magic 

86 def custom_magic_command(self, line): 

87 parser = self.get_parser(MagicClass.custom_magic_command_parser, "custom_magic_command") 

88 args = self.get_args(line, parser) 

89 if args is not None: 

90 param = args.param 

91 

92 # .... 

93 """ 

94 try: 

95 args = parser.parse_cmd(line, context=self.Context) 

96 except SystemExit: # pragma: no cover 

97 print_function(parser.format_usage()) 

98 args = None 

99 

100 return args