Parser (#455)

Closes #466.
Closes #465.
Closes #447.
Closes #443.
Closes #346.
Closes #219. 
Closes #539.
Closes #522.

Cargo.toml

@@ -1,10 +1,17 @@
 [workspace]
 resolver = "2"
+default-members = [
+       "nemo",
+    "nemo-cli",
+    "nemo-physical",
+    "nemo-python",
+]
 members = [
     "nemo",
     "nemo-cli",
     "nemo-physical",
     "nemo-python",
+    "nemo-language-server",
     "nemo-wasm",
 ]
 

nemo-cli/Cargo.toml

@@ -20,8 +20,10 @@ clap = { version = "4.0.32", features = [ "derive", "cargo", "env" ] }
 colored = "2"
 env_logger = "*"
 serde_json = "1.0.108"
+thiserror = "1.0"
 
 nemo = { path = "../nemo" }
+ariadne = "0.4.1"
 
 [dev-dependencies]
 assert_cmd = "2.0"

nemo-cli/src/cli.rs

@@ -105,9 +105,9 @@ pub(crate) struct OutputArgs {
 
 impl OutputArgs {
     /// Creates an output file manager with the current options
-    pub(crate) fn export_manager(self) -> Result<ExportManager, Error> {
-        let export_manager = ExportManager::new()
-            .set_base_path(self.export_directory)
+    pub(crate) fn export_manager(&self) -> Result<ExportManager, Error> {
+        let export_manager = ExportManager::default()
+            .set_base_path(self.export_directory.clone())
             .overwrite(self.overwrite)
             .compress(self.gz);
         Ok(export_manager)
@@ -120,11 +120,11 @@ pub(crate) struct TracingArgs {
     /// Facts for which a derivation trace should be computed;
     /// multiple facts can be separated by a semicolon, e.g. "P(a, b);Q(c)".
     #[arg(long = "trace", value_delimiter = ';', group = "trace-input")]
-    pub(crate) facts_to_be_traced: Option<Vec<String>>,
+    pub(crate) facts: Option<Vec<String>>,
     /// Specify one or multiple input files for the facts that should be traced.
     /// The file format is the same as for the "trace" CLI argument.
     #[arg(long = "trace-input-file", value_parser, group = "trace-input")]
-    pub(crate) trace_input_file: Option<Vec<PathBuf>>,
+    pub(crate) input_file: Option<Vec<PathBuf>>,
     /// File to export the trace to
     #[arg(long = "trace-output", requires = "trace-input")]
     pub(crate) output_file: Option<PathBuf>,

nemo-cli/src/error.rs

@@ -0,0 +1,46 @@
+//! This module defines all the errors that can occur while executing nemo-cli.
+
+use thiserror::Error;
+
+/// Error that occur during execution of Nemo's CLI app
+#[derive(Error, Debug)]
+pub enum CliError {
+    /// Error if no input rule files are specified
+    #[error("no input file was given")]
+    NoInput,
+    /// Error if the user asked for an unimplemented feature
+    #[error("multiple rule files are currently unsupported")]
+    MultipleFilesNotImplemented,
+    /// Error while serializing data to a file
+    #[error("Error while serializing data to {filename}.")]
+    SerializationError {
+        /// Name of the file where data could not have been serialized into
+        filename: String,
+    },
+    /// Errors on reading a file
+    #[error("failed to read `{filename}`: {error}")]
+    IoReading {
+        /// Contains the wrapped error
+        error: std::io::Error,
+        /// Filename which caused the error
+        filename: String,
+    },
+    /// Error while parsing fact for tracing
+    #[error("unable to parse fact: {fact}")]
+    TracingInvalidFact {
+        /// Incorrectly formatted fact
+        fact: String,
+    },
+    /// Error while parsing a rule file
+    #[error("unable to parse program `{filename}`")]
+    ProgramParsing {
+        /// Filename of the rule file
+        filename: String,
+    },
+    /// Error resulting from io operations
+    #[error(transparent)]
+    IoError(#[from] std::io::Error),
+    /// Error originating from nemo
+    #[error(transparent)]
+    NemoError(#[from] nemo::error::Error),
+}