Condition Grammar

• • Basic conditional judgment unit, which defines the primitive of comparison

  • e.g.

• Condition Expression

  • Expression using “and/or/not” to connect condition primitive

  • e.g.

• • Variable that is defined by Condition Expression

  • e.g.

• Advanced Condition Expression

  • Expression using “and/or/not” to connect condition primitive and condition variable

  • In advanced condition expression, condition variable is identified by “$” prefix

  • $news_host && req_method_in("GET") # match condition variable and HTTP method is "GET"

• Basic conditional judgment unit, format is shown as follows:

​ FuncName( params )

• Condition primitive like function definition: FuncName is name of condition primitive; params are input parameters
• Note: All builtin condition primitives

Condition Expression grammar is defined as follows:

• Priority and combination rule of “&&/||/!” is same as them in C language

• Expression description

Advanced Condition Expression grammar is defined as follows:

• Expression description

  Advanced Condition Expression(ACE) -> 
                   | ACE || ACE
                   | ( ACE)
                   | Condition Variable