question: Please tell me the meaning of 255.

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question: Please tell me the meaning of 255. #2583

Open itcuihao opened 3 years ago

itcuihao commented 3 years ago

With issues: Please tell me the meaning of 255.

Description

How to reproduce

func countParams(path string) uint8 {
    var n uint
    for i := 0; i < len(path); i++ {
        if path[i] != ':' && path[i] != '*' {
            continue
        }
        n++
    }
    if n >= 255 {
        return 255
    }
    return uint8(n)
}

go version:go version go1.13 windows/amd64
gin version (or commit ref): master
operating system:

Doarakko commented 3 years ago

uint8 is unsigned integer 8 bit. 8 bits can represent 0 to 255(2**8-1)

itcuihao commented 3 years ago

Does it mean that the length of path cannot exceed 255? Why is it so set?

cpl commented 3 years ago

If I am reading the function correctly, it's counting the named params (:name, :id in the defined path) and not the path length. Check the function usage to understand the possible limtations around it.

yeqown commented 3 years ago

there isn't 255 anymore 😂

https://github.com/gin-gonic/gin/blob/b01605bb5b43dbf33781970af5ad6633e5549fd1/tree_test.go#L87-94