add fs (#34)

fs/fs.mbti

@@ -0,0 +1,17 @@
+package moonbitlang/x/fs
+
+// Values
+fn exists(~path : String) -> Bool
+
+fn read_to_string(~path : String) -> String!
+
+fn write_string(~path : String, ~content : String) -> Unit
+
+// Types and methods
+
+// Type aliases
+
+// Traits
+
+// Extension Methods
+

fs/fs.wasm-gc.mbt

@@ -0,0 +1,86 @@
+// Copyright 2024 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// Reads the contents of a file into a string.
+///
+/// # Parameters
+/// - `path`: An `XExternString` representing the file path.
+///
+/// # Returns
+/// An `XExternString` containing the file contents.
+///
+/// # Note
+/// This is an unstable function call and should be used internally only.
+fn read_file_to_string(path : @ffi.XExternString) -> @ffi.XExternString = "__moonbit_fs_unstable" "read_file_to_string"
+
+/// Writes a string to a file.
+///
+/// # Parameters
+/// - `path`: An `XExternString` representing the file path.
+/// - `content`: An `XExternString` containing the content to be written to the file.
+///
+/// # Note
+/// This is an unstable function call and should be used internally only.
+fn _write_string(path : @ffi.XExternString, content : @ffi.XExternString) = "__moonbit_fs_unstable" "write_string_to_file"
+
+/// Checks if a path exists.
+///
+/// # Parameters
+/// - `path`: An `XExternString` representing the file path.
+///
+/// # Returns
+/// A boolean indicating whether the path exists.
+///
+/// # Note
+/// This is an unstable function call and should be used internally only.
+fn path_exists(path : @ffi.XExternString) -> Bool = "__moonbit_fs_unstable" "path_exists"
+
+fn _read_to_string(path : String) -> String {
+  let content = read_file_to_string(@ffi.string_to_extern(path))
+  @ffi.string_from_extern(content)
+}
+
+/// Writes a string to a file.
+///
+/// # Parameters
+/// - `path`: A `String` representing the file path.
+/// - `content`: A `String` containing the content to be written to the file.
+pub fn write_string(~path : String, ~content : String) -> Unit {
+  _write_string(@ffi.string_to_extern(path), @ffi.string_to_extern(content))
+}
+
+/// Checks if a path exists.
+///
+/// # Parameters
+/// - `path`: A `String` representing the file path.
+///
+/// # Returns
+/// A boolean indicating whether the path exists.
+pub fn exists(~path : String) -> Bool {
+  path_exists(@ffi.string_to_extern(path))
+}
+
+/// Reads the entire contents of a file into a string.
+///
+/// # Parameters
+/// - `path`: A `String` representing the file path.
+///
+/// # Returns
+/// A `String` containing the file contents if the file exists, otherwise raises an error.
+pub fn read_to_string(~path : String) -> String! {
+  if not(exists(~path)) {
+    fail!("File does not exist")
+  }
+  _read_to_string(path)
+}

fs/internal/ffi/array.wasm-gc.mbt

@@ -0,0 +1,23 @@
+// Copyright 2024 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+pub type XJSArray
+
+pub fn array_len(arr : XJSArray) -> Int = "__moonbit_fs_unstable" "array_len"
+
+pub fn array_get(arr : XJSArray, idx : Int) -> XJSValue = "__moonbit_fs_unstable" "array_get"
+
+pub fn XJSArray::op_get(self : XJSArray, idx : Int) -> XJSValue {
+  return array_get(self, idx)
+}

fs/internal/ffi/ffi.mbti

@@ -0,0 +1,35 @@
+package moonbitlang/x/fs/internal/ffi
+
+// Values
+fn array_get(XJSArray, Int) -> XJSValue
+
+fn array_len(XJSArray) -> Int
+
+fn jsvalue_get_string(XJSValue) -> XExternString
+
+fn jsvalue_is_string(XJSValue) -> Bool
+
+fn string_from_extern(XExternString) -> String
+
+fn string_to_extern(String) -> XExternString
+
+// Types and methods
+pub type XExternString
+
+pub type XJSArray
+impl XJSArray {
+  op_get(Self, Int) -> XJSValue
+}
+
+type XJSValue
+
+type XStringCreateHandle
+
+type XStringReadHandle
+
+// Type aliases
+
+// Traits
+
+// Extension Methods
+

fs/internal/ffi/jsvalue.wasm-gc.mbt

@@ -0,0 +1,19 @@
+// Copyright 2024 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+type XJSValue
+
+pub fn jsvalue_is_string(v : XJSValue) -> Bool = "__moonbit_fs_unstable" "jsvalue_is_string"
+
+pub fn jsvalue_get_string(v : XJSValue) -> XExternString = "%identity"

fs/internal/ffi/moon.pkg.json

@@ -0,0 +1 @@
+{}

fs/internal/ffi/string.wasm-gc.mbt

@@ -0,0 +1,54 @@
+// Copyright 2024 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+type XStringCreateHandle
+
+type XStringReadHandle
+
+pub type XExternString
+
+fn begin_create_string() -> XStringCreateHandle = "__moonbit_fs_unstable" "begin_create_string"
+
+fn string_append_char(handle : XStringCreateHandle, ch : Char) = "__moonbit_fs_unstable" "string_append_char"
+
+fn finish_create_string(handle : XStringCreateHandle) -> XExternString = "__moonbit_fs_unstable" "finish_create_string"
+
+pub fn string_to_extern(s : String) -> XExternString {
+  let handle = begin_create_string()
+  s.iter().each(fn(ch) { string_append_char(handle, ch) })
+  finish_create_string(handle)
+}
+
+fn begin_read_string(s : XExternString) -> XStringReadHandle = "__moonbit_fs_unstable" "begin_read_string"
+
+/// Read one char from the string, returns -1 if the end of the string is reached.
+/// The number returned is the unicode codepoint of the character.
+fn string_read_char(handle : XStringReadHandle) -> Int = "__moonbit_fs_unstable" "string_read_char"
+
+fn finish_read_string(handle : XStringReadHandle) = "__moonbit_fs_unstable" "finish_read_string"
+
+pub fn string_from_extern(e : XExternString) -> String {
+  let buf = Buffer::new()
+  let handle = begin_read_string(e)
+  while true {
+    let ch = string_read_char(handle)
+    if ch == -1 {
+      break
+    } else {
+      buf.write_char(Char::from_int(ch))
+    }
+  }
+  finish_read_string(handle)
+  buf.to_string()
+}

fs/internal/internal.mbti

@@ -0,0 +1,12 @@
+package moonbitlang/x/fs/internal
+
+// Values
+
+// Types and methods
+
+// Type aliases
+
+// Traits
+
+// Extension Methods
+

fs/internal/moon.pkg.json

@@ -0,0 +1 @@
+{}

fs/moon.pkg.json

@@ -0,0 +1,5 @@
+{
+    "import": [
+        "moonbitlang/x/fs/internal/ffi"
+    ]
+}