/// <summary>
/// Attempt to evaluate token as a bool, int, etc.
/// Returns null if it fails
/// </summary>
internal static Value DoNoThrow(Token token)
{
string s = token.Value;
// try as nil
if (s == "nil")
return new ValueNil();
// try as bool
if (s == "true")
return new ValueBool(true);
if (s == "false")
return new ValueBool(false);
// try as int
int i;
if (Int32.TryParse(s, out i))
return new ValueInt(i);
// try as float
double d;
if (Double.TryParse(s, out d))
return new ValueFloat(d);
// try as string
// todo: replace with a prefix definition in bootstrap
if (s.StartsWith(":"))
return new ValueString(s.Substring(1));
if (s.StartsWith("->"))
return new ValueString(s.Substring(2));
// give up
return null;
}
/// <summary>
/// Attempt to evaluate token as a bool, int, etc. May throw.
/// </summary>
internal static Value Do(Token token)
{
Value v = DoNoThrow(token);
if (v == null)
throw new Loki3Exception().AddBadToken(token);
return v;
}
public Value GetValue(Token token)
{
Value val;
if (m_values.TryGetValue(token.Value, out val))
return val;
return (m_parent != null ? m_parent.GetValue(token) : null);
}
internal DelimiterNodeToken(Token token)
{
m_token = token;
}
/// <summary>If :key is present, lookup value, else if :value is present, return value.</summary>
internal static Value GetFromKeyOrValue(Map map, IScope scope)
{
// either lookup up value w/ specified key or just get specified value
Value value = null;
Value key = map["key"];
if (key != ValueNil.Nil)
{
Token token = new Token(key.AsString);
value = scope.GetValue(token);
if (value == null)
throw new Loki3Exception().AddBadToken(token);
}
else if (map.ContainsKey("value"))
{
value = map["value"];
}
if (value == null)
// todo: better error
throw new Loki3Exception().AddMissingKey(new ValueString("key or value required"));
return value;
}
/// <summary>Could not parse token</summary>
internal Loki3Exception AddBadToken(Token token)
{
m_map[keyBadToken] = new ValueString(token.Value);
return this;
}
// simply search for end and stuff everything in the middle into a single token
private static bool ParseString(int indent, string[] strs, int iStart,
ValueDelimiter thisDelim, List<DelimiterNode> nodes,
out int iEnd, out DelimiterList result)
{
iEnd = -1;
bool bExtra = false;
for (int i = iStart; i < strs.Length; i++)
{
string s = strs[i];
if (s == thisDelim.End)
{
iEnd = i;
break;
}
else if (s.Substring(s.Length - 1, 1) == thisDelim.End)
{
iEnd = i + 1;
bExtra = true;
break;
}
}
// no specified end delim means take the remainder of the line
if (thisDelim.End == "")
iEnd = strs.Length;
// if we found end, wrap entire string in a single node
if (iEnd != -1)
{
string subStr = GetSubStr(iStart, iEnd, strs);
if (bExtra)
{
subStr = subStr.Substring(0, subStr.Length - 1);
--iEnd;
}
Token token = new Token(subStr);
DelimiterNode node = new DelimiterNodeToken(token);
nodes.Add(node);
result = new DelimiterList(thisDelim, nodes, indent, strs[iStart - 1], subStr, null);
return true;
}
result = null;
return false;
}
// handle as individual tokens and nested lists
private static bool ParseMisc(int indent, string original, string[] strs, int iStart, ValueDelimiter thisDelim,
IParseLineDelimiters delims, ILineRequestor requestor, List<DelimiterNode> nodes,
out int iEnd, out DelimiterList result)
{
result = null;
iEnd = strs.Length;
for (int i = iStart; i < strs.Length; i++)
{
string s = strs[i];
// is this the end of current set of delimited tokens?
if (s == thisDelim.End)
{ // end delimiter
iEnd = i;
string subStr = GetSubStr(iStart, iEnd, strs);
result = new DelimiterList(thisDelim, nodes, indent, strs[iStart - 1], subStr, null);
return true;
}
// TODO: rework this so I don't need to check for : (e.g. for :}, when creating a delim)
if (s.Substring(s.Length - 1, 1) == thisDelim.End && (s[0] != ':' || s.Length > 2))
{ // end delimiter is part of final token
iEnd = i + 1;
string without = s.Substring(0, s.Length - 1);
Token token = new Token(without);
DelimiterNode node = new DelimiterNodeToken(token);
nodes.Add(node);
strs[i] = without;
string subStr = GetSubStr(iStart, iEnd, strs);
result = new DelimiterList(thisDelim, nodes, indent, strs[iStart - 1], subStr, null);
strs[i] = s;
--iEnd;
return true;
}
// is it a stand alone starting delimiter?
bool bAnyToken = false;
ValueDelimiter subDelim = (delims == null ? null : delims.GetDelim(s, out bAnyToken));
string[] strsToUse = strs;
bool bExtra = true;
if (subDelim == null && !bAnyToken)
{ // whole thing wasn't a delimiter, function, etc., how about the 1st char?
string s1 = s.Substring(0, 1);
subDelim = (delims == null ? null : delims.GetDelim(s1, out bAnyToken));
if (subDelim != null)
{ // copy across array, but break iStart into delim & remainder
bExtra = false;
strsToUse = new string[strs.Length + 1];
for (int j = 0; j < i; j++)
strsToUse[j] = strs[j];
strsToUse[i] = s1;
strsToUse[i + 1] = s.Substring(1);
for (int j = i + 1; j < strs.Length; j++)
strsToUse[j + 1] = strs[j];
}
}
if (subDelim != null)
{ // start delimiter
int end;
DelimiterList sublist = Do(0, original, strsToUse, i + 1, subDelim, delims, requestor, out end);
if (sublist != null)
{
DelimiterNodeList node = new DelimiterNodeList(sublist);
nodes.Add(node);
}
// skip past the sublist
i = (bExtra ? end : end - 1);
}
else
{ // stand alone token
Token token = new Token(s);
DelimiterNode node = new DelimiterNodeToken(token);
nodes.Add(node);
}
}
return false;
}
