Add some more text utilities

src/lang/text/include/sourcemeta/core/text.h

@@ -191,6 +191,31 @@ inline constexpr auto is_alpha(const Character character) noexcept -> bool {
          (character >= 'A' && character <= 'Z');
 }
 
+/// @ingroup text
+///
+/// Return whether a string is non-empty and consists entirely of ASCII letters
+/// (A-Z or a-z). An empty string is not considered a match. For example:
+///
+/// ```cpp
+/// #include <sourcemeta/core/text.h>
+/// #include <cassert>
+///
+/// assert(sourcemeta::core::is_alpha("abc"));
+/// assert(!sourcemeta::core::is_alpha("ab1"));
+/// assert(!sourcemeta::core::is_alpha(""));
+/// ```
+inline constexpr auto is_alpha(const std::string_view value) noexcept -> bool {
+  if (value.empty()) {
+    return false;
+  }
+  for (const auto character : value) {
+    if (!is_alpha(character)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 /// @ingroup text
 ///
 /// Return whether a character is an ASCII digit (0-9). For example:
@@ -211,6 +236,31 @@ inline constexpr auto is_digit(const Character character) noexcept -> bool {
   return character >= '0' && character <= '9';
 }
 
+/// @ingroup text
+///
+/// Return whether a string is non-empty and consists entirely of ASCII digits
+/// (0-9). An empty string is not considered a match. For example:
+///
+/// ```cpp
+/// #include <sourcemeta/core/text.h>
+/// #include <cassert>
+///
+/// assert(sourcemeta::core::is_digit("123"));
+/// assert(!sourcemeta::core::is_digit("12a"));
+/// assert(!sourcemeta::core::is_digit(""));
+/// ```
+inline constexpr auto is_digit(const std::string_view value) noexcept -> bool {
+  if (value.empty()) {
+    return false;
+  }
+  for (const auto character : value) {
+    if (!is_digit(character)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 /// @ingroup text
 ///
 /// Return whether a character is an ASCII letter or digit. For example:
@@ -232,6 +282,32 @@ inline constexpr auto is_alphanum(const Character character) noexcept -> bool {
   return is_alpha(character) || is_digit(character);
 }
 
+/// @ingroup text
+///
+/// Return whether a string is non-empty and consists entirely of ASCII letters
+/// or digits. An empty string is not considered a match. For example:
+///
+/// ```cpp
+/// #include <sourcemeta/core/text.h>
+/// #include <cassert>
+///
+/// assert(sourcemeta::core::is_alphanum("abc123"));
+/// assert(!sourcemeta::core::is_alphanum("abc-123"));
+/// assert(!sourcemeta::core::is_alphanum(""));
+/// ```
+inline constexpr auto is_alphanum(const std::string_view value) noexcept
+    -> bool {
+  if (value.empty()) {
+    return false;
+  }
+  for (const auto character : value) {
+    if (!is_alphanum(character)) {
+      return false;
+    }
+  }
+  return true;
+}
+
 /// @ingroup text
 ///
 /// Truncate a string in place to at most `maximum_length` bytes, appending

test/text/text_is_alpha_test.cc

@@ -32,3 +32,19 @@ TEST(Text_is_alpha, ascii_boundaries) {
   EXPECT_FALSE(sourcemeta::core::is_alpha('`'));
   EXPECT_FALSE(sourcemeta::core::is_alpha('{'));
 }
+
+TEST(Text_is_alpha, string_all_letters) {
+  EXPECT_TRUE(sourcemeta::core::is_alpha("abcXYZ"));
+}
+
+TEST(Text_is_alpha, string_with_digit) {
+  EXPECT_FALSE(sourcemeta::core::is_alpha("abc1"));
+}
+
+TEST(Text_is_alpha, string_with_punctuation) {
+  EXPECT_FALSE(sourcemeta::core::is_alpha("ab-cd"));
+}
+
+TEST(Text_is_alpha, empty_string) {
+  EXPECT_FALSE(sourcemeta::core::is_alpha(""));
+}

test/text/text_is_alphanum_test.cc

@@ -18,3 +18,15 @@ TEST(Text_is_alphanum, punctuation) {
   EXPECT_FALSE(sourcemeta::core::is_alphanum('.'));
   EXPECT_FALSE(sourcemeta::core::is_alphanum(' '));
 }
+
+TEST(Text_is_alphanum, string_letters_and_digits) {
+  EXPECT_TRUE(sourcemeta::core::is_alphanum("abc123XYZ"));
+}
+
+TEST(Text_is_alphanum, string_with_punctuation) {
+  EXPECT_FALSE(sourcemeta::core::is_alphanum("abc-123"));
+}
+
+TEST(Text_is_alphanum, empty_string) {
+  EXPECT_FALSE(sourcemeta::core::is_alphanum(""));
+}

test/text/text_is_digit_test.cc

@@ -23,3 +23,15 @@ TEST(Text_is_digit, ascii_boundaries) {
   EXPECT_FALSE(sourcemeta::core::is_digit('/'));
   EXPECT_FALSE(sourcemeta::core::is_digit(':'));
 }
+
+TEST(Text_is_digit, string_all_digits) {
+  EXPECT_TRUE(sourcemeta::core::is_digit("0123456789"));
+}
+
+TEST(Text_is_digit, string_with_letter) {
+  EXPECT_FALSE(sourcemeta::core::is_digit("12a"));
+}
+
+TEST(Text_is_digit, empty_string) {
+  EXPECT_FALSE(sourcemeta::core::is_digit(""));
+}