checking in before refactoring interpolation

envs/consts.go

@@ -9,3 +9,25 @@ var (
 	reMaybeInt   *regexp.Regexp = regexp.MustCompile(`^(?P<sign>\+|-)[0-9]+$`)
 	reMaybeFloat *regexp.Regexp = regexp.MustCompile(`(?P<sign>\+|-)?[0-9]+\.[0-9]+$`)
 )
+
+var (
+	StructTagInterpolate string = "envsub"
+	StructTagPopulate    string = "envpop"
+)
+
+var (
+	defaultInterpolateOpts interpolateOpts = interpolateOpts{
+		noMapKey: false,
+		noMapVal: false,
+	}
+	// InterpolateOptNoMapKey is the equivalent of the struct tag `no_map_key` for Interpolate.
+	InterpolateOptNoMapKey optInterpolate = func(o *interpolateOpts) (err error) {
+		o.noMapKey = true
+		return
+	}
+	// InterpolateOptNoMapValue is the equivalent of the struct tag `no_map_value` for Interpolate.
+	InterpolateOptNoMapValue optInterpolate = func(o *interpolateOpts) (err error) {
+		o.noMapVal = true
+		return
+	}
+)