void readNumber(Token.Pos tp, char first)
{
var seenDot = first == '.';
while (pos < len)
{
var c = code[pos];
if (c >= '0' && c <= '9')
{
pos++;
}
else if (c == '.')
{
if (seenDot)
{
break;
}
seenDot = true;
pos++;
}
else
{
break;
}
}
add(new Token.Number(tp, slice(tp.pos, pos)));
}
public For(Token.Pos tp, Node init, Node cond, Node post, Node loop) : base(tp)
{
this.init = init;
this.cond = cond;
this.post = post;
this.loop = loop;
}
/// <summary>
/// Reading `<` or `<=` accordingly
/// </summary>
void readCmpOp(Token.Pos tp, Token.BinOpType opEq, Token.BinOpType op)
{
if (pos < len && code[pos] == '=')
{
pos++;
add(new Token.BinOp(tp, opEq));
}
else
{
add(new Token.BinOp(tp, op));
}
}
public Source(string _name, string _code)
{
name = _name;
code = _code;
start = new Token.Pos(this, 0, 0, 0);
{
var row = 0;
int np = 0;
var lastRowStart = 0;
while ((np = _code.IndexOf('\n', np)) != -1)
{
lastRowStart = np++;
row++;
}
end = new Token.Pos(this, _code.Length, row, _code.Length - lastRowStart);
};
}
public If(Token.Pos tp, Node @if, Node then, Node @else) : base(tp)
{
this.@if = @if;
this.then = then;
this.@else = @else;
}
public UnOp(Token.Pos tp, Token.UnOpType type, Node node) : base(tp)
{
this.type = type;
this.node = node;
}
public Call(Token.Pos tp, Node node) : base(tp)
{
this.node = node;
}
public Return(Token.Pos tp, Node node) : base(tp)
{
this.node = node;
}
public ArrayLiteral(Token.Pos tp) : base(tp)
{
}
public ArrayAccess(Token.Pos tp, Node node, Node index) : base(tp)
{
this.node = node; this.index = index;
}
public Var(Token.Pos tp, string name, Node value) : base(tp)
{
this.name = name;
this.value = value;
}
public List <Token> parse(Source _source)
{
tokens = new List <Token>();
source = _source;
pos = 0;
len = _source.code.Length;
code = _source.code + "\x1B";
//
var rowStart = 0;
var row = 0;
while (pos < len)
{
var start = pos;
var tp = new Token.Pos(_source, pos, row, pos - rowStart);
switch (code[pos++])
{
case ' ':
case '\t':
case '\r': break;
case '\n':
row++;
rowStart = pos;
break;
case '(': add(new Token.ParOpen(tp)); break;
case ')': add(new Token.ParClose(tp)); break;
case '[': add(new Token.SquareOpen(tp)); break;
case ']': add(new Token.SquareClose(tp)); break;
case '{': add(new Token.CurlyOpen(tp)); break;
case '}': add(new Token.CurlyClose(tp)); break;
case ';': add(new Token.Semico(tp)); break;
case ',': add(new Token.Comma(tp)); break;
case '+': readBinOp(tp, Token.BinOpType.Add); break;
case '-': readBinOp(tp, Token.BinOpType.Subtract); break;
case '%': readBinOp(tp, Token.BinOpType.Modulo); break;
case '~': add(new Token.UnOp(tp, Token.UnOpType.BitNot)); break;
case '*':
if (code[pos] == '*')
{
pos++;
readBinOp(tp, Token.BinOpType.Power);
}
else
{
readBinOp(tp, Token.BinOpType.Multiply);
}
break;
case '/':
if (code[pos] == '*')
{
pos += 1;
while (pos < len - 1)
{
if (code[pos] == '*' && code[pos + 1] == '/')
{
pos += 2;
break;
}
else
{
pos += 1;
}
}
}
else if (code[pos] == '/') // comment!
{
while (pos < len)
{
if (code[pos] == '\n')
{
break;
}
pos += 1;
}
}
else
{
readBinOp(tp, Token.BinOpType.Divide);
}
break;
case '<':
if (code[pos] == '<')
{
pos++;
readBinOp(tp, Token.BinOpType.BitShiftLeft);
}
else
{
readCmpOp(tp, Token.BinOpType.LessThanOrEqual, Token.BinOpType.LessThan);
}
break;
case '>':
if (code[pos] == '>')
{
pos++;
readBinOp(tp, Token.BinOpType.BitShiftRight);
}
else
{
readCmpOp(tp, Token.BinOpType.GreaterThanOrEqual, Token.BinOpType.GreaterThan);
}
break;
case '=':
if (code[pos] == '=')
{
pos++;
add(new Token.BinOp(tp, Token.BinOpType.Equals));
}
else
{
add(new Token.SetOp(tp, Token.BinOpType.Set));
}
break;
case '!':
if (code[pos] == '=')
{
pos++;
add(new Token.BinOp(tp, Token.BinOpType.NotEquals));
}
else
{
add(new Token.UnOp(tp, Token.UnOpType.Not));
}
break;
case '"': // a string! with escape characters!
var sb = new StringBuilder();
var strFound = false;
while (pos < len)
{
var c = code[pos++];
if (c == '"')
{
strFound = true;
add(new Token.CString(tp, sb.ToString()));
break;
}
else if (c == '\\')
{
switch (code[pos++])
{
case 'r': sb.Append('\r'); break;
case 'n': sb.Append('\n'); break;
case 't': sb.Append('\t'); break;
case 'b': sb.Append('\b'); break;
case '"': sb.Append('"'); break;
case 'x':
var hc = (char)int.Parse(code.Substring(pos, 2), System.Globalization.NumberStyles.HexNumber);
sb.Append(hc);
pos += 2;
break;
case '\\': sb.Append('\\'); break;
case var c1: sb.Append(c1); break;
}
}
else
{
sb.Append(c);
}
}
if (!strFound)
{
throw new Exception($"Unclosed string starting at ${tp}");
}
break;
case '.': // . or .1
if (code[pos] >= '0' && code[pos] <= '9')
{
readNumber(tp, '.');
}
else
{
add(new Token.Period(tp));
}
break;
case var c when c == '0' && code[pos] == 'x': // hex literal!
pos++;
while (pos < len)
{
c = code[pos];
if (c >= '0' && c <= '9' || c >= 'a' && c <= 'f' || c >= 'A' && c <= 'F')
{
pos++;
}
else
{
break;
}
}
add(new Token.Number(tp, slice(start, pos)));
break;
case var c when c >= '0' && c <= '9': // decimal!
readNumber(tp, c);
break;
case var c when c == '_' || c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z': // words!
while (pos < len)
{
c = code[pos];
if (c == '_' || c >= '0' && c <= '9' || c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z')
{
pos++;
}
else
{
break;
}
}
//
var word = slice(start, pos);
if (keywordMap.TryGetValue(word, out var fn))
{
add(fn(tp, word));
}
else
{
add(new Token.Ident(tp, word));
}
break;
case var c: throw new Exception($"Unknown character `{c}`");
}
}
add(new Token.EOF(_source.end));
return(tokens);
}
public While(Token.Pos tp, Node cond, Node loop) : base(tp)
{
this.cond = cond;
this.loop = loop;
}
public Break(Token.Pos tp) : base(tp)
{
}
public Field(Token.Pos tp, Node node, string field) : base(tp)
{
this.field = field;
this.node = node;
}
public Local(Token.Pos tp, string text) : base(tp, text)
{
}
public Ident(Token.Pos tp, string text) : base(tp, text)
{
}
public CString(Token.Pos tp, string text) : base(tp, text)
{
}
public Number(Token.Pos tp, string text) : base(tp, text)
{
}
public DoWhile(Token.Pos tp, Node loop, Node cond) : base(tp)
{
this.loop = loop;
this.cond = cond;
}
public Node(Token.Pos tp)
{
pos = tp;
}
public Continue(Token.Pos tp) : base(tp)
{
}
public SetOp(Token.Pos tp, Token.BinOpType type, Node left, Node right) : base(tp)
{
this.type = type;
this.left = left;
this.right = right;
}
public Literal(Token.Pos tp, string value) : base(tp)
{
this.value = value;
}
public Block(Token.Pos tp) : base(tp)
{
}