constraint: example of forcing an error for impossible builds

boolean/boolean.go

@@ -1,14 +1,14 @@
 // boolean.go
 package bocchi
 
-import "git.sunturtle.xyz/zephyr/errors-my-beloved/boolean/secret"
+import "git.sunturtle.xyz/zephyr/errors-my-beloved/boolean/challenge"
 
 var _ = map[bool]struct{}{
 	false:                      {},
-	secret.Secret == "gc25{}": {}, // ERROR: ./boolean.go:7:2: duplicate key false in map literal
+	challenge.Flag == "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
+	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 to build. 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
 )