Move trivial template functions into misc

1 files changed, 48 insertions, 0 deletions

diff --git a/internal/misc/trivial.go b/internal/misc/trivial.go
new file mode 100644
index 0000000..e59c17e
--- /dev/null
+++ b/internal/misc/trivial.go
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: AGPL-3.0-only
+// SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>
+
+package misc
+
+import (
+	"net/url"
+	"strings"
+)
+
+// These are all trivial functions that are intended to be used in HTML
+// templates.
+
+// FirstLine returns the first line of a string.
+func FirstLine(s string) string {
+	before, _, _ := strings.Cut(s, "\n")
+	return before
+}
+
+// PathEscape escapes the input as an URL path segment.
+func PathEscape(s string) string {
+	return url.PathEscape(s)
+}
+
+// QueryEscape escapes the input as an URL query segment.
+func QueryEscape(s string) string {
+	return url.QueryEscape(s)
+}
+
+// Dereference dereferences a pointer.
+func Dereference[T any](p *T) T {
+	return *p
+}
+
+// DereferenceOrZero dereferences a pointer. If the pointer is nil, the zero
+// value of its associated type is returned instead.
+func DereferenceOrZero[T any](p *T) T {
+	if p != nil {
+		return *p
+	}
+	var z T
+	return z
+}
+
+// Minus subtracts two numbers.
+func Minus(a, b int) int {
+	return a - b
+}