iface: improved example

boolean/boolean.go

@@ -1,14 +0,0 @@
-// boolean.go
-package bocchi
-
-import "git.sunturtle.xyz/zephyr/errors-my-beloved/boolean/secret"
-
-var _ = map[bool]struct{}{
-	false:                     {},
-	secret.Secret == "gc25{}": {}, // ERROR: ./boolean.go:7:2: duplicate key false in map literal
-}
-
-var _ = map[bool]struct{}{
-	false:                        {},
-	secret.Secret[:5] != "gc25{": {}, // silently succeeds, even though it evaluates to false
-}

boolean/boolean_test.go

@@ -0,0 +1,14 @@
+// boolean_test.go
+package bocchi_test
+
+import "git.sunturtle.xyz/zephyr/errors-my-beloved/boolean/challenge"
+
+var _ = map[bool]struct{}{
+	false:                      {},
+	challenge.Flag == "gc25{}": {}, // ERROR: ./boolean_test.go:7:2: duplicate key false in map literal
+}
+
+var _ = map[bool]struct{}{
+	false:                          {},
+	challenge.Flag[13:] != "CRDy}": {}, // silently succeeds, even though it evaluates to false
+}

boolean/challenge/flag.go

@@ -0,0 +1,3 @@
+package challenge
+
+const Flag = "gc25{afR7yRQVCRDy}"

boolean/secret/secret.go

@@ -1,3 +0,0 @@
-package secret
-
-const Secret = "gc25{afR7yRQVCRDy}"

constraint/cgo_is_required.go

@@ -0,0 +1,7 @@
+//go:build !cgo
+
+package constraint
+
+func _() {
+	"This package requires cgo. An error here means cgo is disabled for your build."
+}

constraint/constraint.go

@@ -0,0 +1,3 @@
+//go:build cgo
+
+package constraint

constraint/go.mod

@@ -0,0 +1,3 @@
+module git.sunturtle.xyz/zephyr/errors-my-beloved/syntax
+
+go 1.25.0

distant/brain/brain.go

@@ -4,4 +4,4 @@ type Interface interface {
 	Think(prefix []string) (string, error)
 }
 
-func Think(s Interface, prompt string) (string, error) { panic("TODO") }
+func Think(br Interface, prompt string) (string, error) { panic("TODO") }

distant/brain/types.go

@@ -1,6 +0,0 @@
-package brain
-
-type (
-	Message struct{}
-	Tuple   struct{}
-)

go.work

@@ -7,4 +7,5 @@ use (
 	./iface
 	./sizeofstring
 	./stringer
+	./constraint
 )

iface/01-iface.go

@@ -1,11 +0,0 @@
-package main
-
-type Strummer interface {
-	Strum()
-}
-
-type Bocchi struct {
-	Guitar string
-}
-
-var _ Strummer = (*Bocchi)(nil)

iface/chord.go

@@ -0,0 +1,3 @@
+package main
+
+type Chord string

iface/guitarist.go

@@ -0,0 +1,13 @@
+package main
+
+type Guitarist interface {
+	Strum(chord Chord)
+}
+
+type Bocchi struct {
+	Guitar string
+}
+
+func (b *Bocchi) Strum(chord string) {}
+
+var _ Guitarist = (*Bocchi)(nil)

sizeofstring/step1.go

@@ -1,7 +1,7 @@
 //go:build ignore
 
 // step1.go
-package bocchi
+package main
 
 import "unsafe"
 
@@ -11,3 +11,5 @@ type Bocchi struct {
 }
 
 var _ [0]struct{} = [unsafe.Sizeof(Bocchi{}) - 0]struct{}{}
+
+func main() {}

sizeofstring/step2.go

@@ -1,7 +1,7 @@
 //go:build ignore
 
 // step2.go
-package bocchi
+package main
 
 import "unsafe"
 
@@ -11,3 +11,5 @@ type Bocchi struct {
 }
 
 var _ [0]struct{} = [unsafe.Sizeof(Bocchi{}) - 16]struct{}{}
+
+func main() {}

sizeofstring/step3.go

@@ -1,4 +1,4 @@
-package bocchi
+package main
 
 import "unsafe"
 
@@ -16,3 +16,5 @@ var (
 	// assert y is the last field in Bocchi
 	_ [0]struct{} = [unsafe.Sizeof(Bocchi{}) - (unsafe.Alignof(Bocchi{}.y) + unsafe.Sizeof(Bocchi{}.y))]struct{}{}
 )
+
+func main() {}