modernc.org/gc@v1.0.1-0.20240304020402-f0dba7c97c2b/testdata/errchk/test/const5.go (about)

     1  // errorcheck
     2  
     3  // Copyright 2011 The Go Authors. All rights reserved.
     4  // Use of this source code is governed by a BSD-style
     5  // license that can be found in the LICENSE file.
     6  
     7  // Test that len non-constants are not constants, https://golang.org/issue/3244.
     8  
     9  package p
    10  
    11  var b struct {
    12  	a[10]int
    13  }
    14  
    15  var m map[string][20]int
    16  
    17  var s [][30]int
    18  
    19  func f() *[40]int
    20  var c chan *[50]int
    21  var z complex128
    22  
    23  const (
    24  	n1 = len(b.a)
    25  	n2 = len(m[""])
    26  	n3 = len(s[10])
    27  
    28  	n4 = len(f())  // ERROR "is not a constant|is not constant"
    29  	n5 = len(<-c) // ERROR "is not a constant|is not constant"
    30  
    31  	n6 = cap(f())  // ERROR "is not a constant|is not constant"
    32  	n7 = cap(<-c) // ERROR "is not a constant|is not constant"
    33  	n8 = real(z) // ERROR "is not a constant|is not constant"
    34  	n9 = len([4]float64{real(z)}) // ERROR "is not a constant|is not constant"
    35  
    36  )
    37