Merge pull request #18 from Lilit0x/functions/ascii

ASCII String Function: #13

crates/gitql-ast/src/function.rs

@@ -24,6 +24,7 @@ lazy_static! {
         map.insert("ltrim", text_left_trim);
         map.insert("rtrim", text_right_trim);
         map.insert("len", text_len);
+        map.insert("ascii", text_ascii);
         map
     };
 }
@@ -94,6 +95,13 @@ lazy_static! {
                 result: DataType::Number,
             },
         );
+        map.insert(
+            "ascii",
+            Prototype {
+                parameters: vec![DataType::Text],
+                result: DataType::Number,
+            },
+        );
         map
     };
 }
@@ -136,3 +144,11 @@ fn text_right_trim(inputs: Vec<Value>) -> Value {
 fn text_len(inputs: Vec<Value>) -> Value {
     return Value::Number(inputs[0].as_text().len() as i64);
 }
+
+fn text_ascii(inputs: Vec<Value>) -> Value {
+    let text = inputs[0].as_text();
+    if text.is_empty() {
+        return Value::Number(0);
+    }
+    return Value::Number(text.chars().nth(0).unwrap() as i64);
+}

docs/function/functions.md

@@ -13,6 +13,7 @@ note that all functions names are case-insensitive.
 | LEN       | Text         | Number | Return the length of this string.                             |
 | REPLICATE | Text, Number | Text   | Return repeated a string a specified number of times.         |
 | SPACE     | Number       | Text   | Returns a string of the specified number of space characters. |
+| ASCII     | Text         | Number | Returns the ASCII value for the specific character.           |
 
 ### String functions samples
 
@@ -23,4 +24,5 @@ SELECT * FROM commits where REVERSE(name) = "repolevedrma"
 SELECT * FROM commits where TRIM(name) = ""
 SELECT * FROM commits where LEN(name) > 0
 SELECT * FROM commits where name = SPACE(5)
+SELECT name, ASCII(name) AS firstCharAscii FROM commits
 ```