18 Exemples d'escapament

Vista general

Aquesta pàgina ofereix exemples d'ús de l'escapada correcta quan s'empren expressions regulars en diversos contextos.

Examples

User macro with context

Regular expression: \.+\"[a-z]+
User macro with context: {$MACRO:regex:"\.+\\"[a-z]+"}

Notice:

• backslashes are not escaped;
• quotation marks are escaped.

LLD macro function

Regular expression: \.+\"[a-z]+
LLD macro: {{#MACRO}.iregsub("\.+\\"[a-z]+", \1)}

Notice:

• backslashes are not escaped;
• quotation marks are escaped.

LLD macro function inside user macro context

Regular expression: \.+\"[a-z]+
LLD macro: {{#MACRO}.iregsub("\.+\\"[a-z]+", \1)}
User macro with context: {$MACRO:"{{#MACRO}.iregsub(\".+\\\"[a-z]+\", \1)}"}

Notice:

• backslash escaping for LLD does not change;
• upon inserting the LLD macro into user macro context, we need to put it into string:

1. Quotation marks are added around the macro expression;
2. Quotation marks get escaped; in total, 3 new backslashes are introduced.

String parameter of function (any)

concat is used as example.

String content: \.+\"[a-z]+
Expression: concat("abc", "\\.\\\"[a-z]+")

Notice:

• String parameters require escaping both for backslashes and quotation marks.

LLD macro function inside string parameter of function

Regular expression: \.+\"[a-z]+
LLD macro: {{#MACRO}.iregsub("\.+\\"[a-z]+", \1)}
Expression: concat("abc, "{{#MACRO}.iregsub(\"\\.+\\\\\"[a-z]+\", \\1)}")

Notice:

• String parameters require escaping both for backslashes and quotation marks;
• Another layer of escaping is added, because the macro will be resolved only after string is unquoted;

User macro with context inside string parameter of function

Regular expression: \.+\"[a-z]+
User macro with context: {$MACRO:regex:"\.+\\"[a-z]+"}
Expression: concat("abc, "{$MACRO:regex:\"\\.+\\\\\"[a-z]+\"}")

Notice:

• Same as in the previous example an additional layer of escaping is needed;
• Backslashes and quotation marks are escaped only for the top-level escaping (by virtue of it being a string parameter).

LLD macro function inside user macro context inside function

Regular expression: \.+\"[a-z]+
LLD macro: {{#MACRO}.iregsub("\.+\\"[a-z]+", \1)}
User macro with context: {$MACRO:"{{#MACRO}.iregsub(\".+\\\"[a-z]+\", \1)}"}
Expression: concat("abc, "{$MACRO:\"{{#MACRO}.iregsub(\\\".+\\\\\\\"[a-z]+\\\", \\1)}\"}")

Notice the three layers of escaping:

1. For LLD macro function, without escaping of backslashes;
2. For User macro with context, without escaping of backslashes;
3. For the string parameter of a function, with escaping of backslashes.

User macro with context just inside string

Regular expression: \.+\"[a-z]+
User macro with context: {$MACRO:regex:"\.+\\"[a-z]+"}
Inside string of some expression, for example: func(arg1, arg2, arg3)="{$MACRO:regex:\"\\.+\\\\\"[a-z]+\"}"

Notice:

• Strings also require backslash escaping;
• Strings also require quotation mark escaping;
• Again a case with 2 levels of escaping:
  1. Escaping for user macro context without backslash escaping;
  2. Escaping for it being a string with backslash escaping.