1 files changed, 52 insertions, 0 deletions
diff --git a/src/parser.rs b/src/parser.rs
new file mode 100644
index 0000000..a6ec7cf
--- /dev/null
+++ b/src/parser.rs
@@ -0,0 +1,52 @@
+use crate::tokenizer::{self, If, Keyword::*, Loop};
+
+pub const EXPRESSION_DELIMITERS: &[char] = &[
+    ';', '{', '}',
+];
+
+#[derive(Clone, Copy, Debug)]
+pub enum Scope {
+    If(If),
+    Loop(Loop),
+}
+
+#[derive(Debug)]
+pub enum Expression<'a> {
+    StartOrStop(bool),
+    Decision((&'a str, Scope)),
+    IO(&'a str),
+    Process(&'a str),
+}
+
+pub fn delimit(str: &str) -> Vec<&str> {
+    str.split(|c| EXPRESSION_DELIMITERS.contains(&c))
+        .filter(|c| !c.is_empty())
+        .collect()
+}
+
+pub fn parse(strs: Vec<&str>) -> Vec<Expression<'_>> {
+    let mut expressions = Vec::new();
+
+    for str in strs {
+        let mut exp: Option<Expression> = None;
+
+        // TODO: fix one line if else as not delimited by {}
+        for s in str.split_whitespace() {
+            if let Some(token) = tokenizer::parse(s) {
+                exp = match token {
+                    If(t) => Some(Expression::Decision((str, Scope::If(t.to_owned())))),
+                    Loop(t) => Some(Expression::Decision((str, Scope::Loop(t.to_owned())))),
+                    Throw => Some(Expression::IO(str)),
+                    IO => Some(Expression::IO(str)),
+                }
+            }
+        }
+
+        match exp {
+            Some(exp) => expressions.push(exp),
+            None => expressions.push(Expression::Process(str)),
+        }
+    }
+
+    expressions
+}