add include directive

README.md

@@ -32,6 +32,8 @@ second {
   key = "value";
   global_reference = sub_settings.sub_float;
   local_reference = .key;  # References second.key
+
+  include "/path/to/other/settings/*.cfg";
 }
 ```
 
@@ -43,6 +45,11 @@ Sections (basically a map) is formatted as the section name with the section's s
 
 Comments start with a pound sign `#` and end with a newline. A comment can exist on the same line as settings/sections, but the comment must end the line.
 
+Includes are allowed simply by using the directive `include` followed by a string pointing to the location of the file(s) you want to include.
+`include` uses go's [filepath.Match](http://golang.org/pkg/path/filepath/#Glob) functionality to find all files matching the provided pattern.
+Each file is included directly where it's `include` statement is called from.
+`include "/etc/app/*.cfg";`
+
 ## Data types
 
 ### Boolean

config/section.go

@@ -6,6 +6,7 @@ type SectionValue struct {
 	Name     string
 	Value    map[string]ConfigValue
 	Comments []string
+	Includes []string
 }
 
 func NewNamedSection(name string) SectionValue {
@@ -13,6 +14,7 @@ func NewNamedSection(name string) SectionValue {
 		Name:     name,
 		Value:    make(map[string]ConfigValue),
 		Comments: make([]string, 0),
+		Includes: make([]string, 0),
 	}
 }
 
@@ -20,6 +22,7 @@ func NewAnonymousSection() SectionValue {
 	return SectionValue{
 		Value:    make(map[string]ConfigValue),
 		Comments: make([]string, 0),
+		Includes: make([]string, 0),
 	}
 }
 
@@ -30,6 +33,10 @@ func (this SectionValue) AddComment(comment string) {
 	this.Comments = append(this.Comments, comment)
 }
 
+func (this SectionValue) AddInclude(include string) {
+	this.Includes = append(this.Includes, include)
+}
+
 func (this SectionValue) Set(name string, value ConfigValue) {
 	this.Value[name] = value
 }

example/example.cfg

@@ -8,6 +8,8 @@ primary {
   boolean = true;
   negative = FALSE;
   nothing = NULL;
+  # Include external files
+  include "./include*.cfg";
   # Primary-sub stuff
   sub {
       key = "primary sub key value";

parser/parser.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
 
@@ -167,7 +168,7 @@ func (this *Parser) parseSetting(name string) error {
 		read_next = false
 	default:
 		return this.SyntaxError(
-			fmt.Sprintf("expected STRING, INTEGER or FLOAT, instead found %s", this.cur_tok.ID),
+			fmt.Sprintf("expected STRING, INTEGER, FLOAT, BOOLEAN or IDENTIFIER, instead found %s", this.cur_tok.ID),
 		)
 	}
 
@@ -184,6 +185,39 @@ func (this *Parser) parseSetting(name string) error {
 	return nil
 }
 
+func (this *Parser) parseInclude() error {
+	if this.cur_tok.ID != token.STRING {
+		msg := fmt.Sprintf("expected STRING instead found '%s'", this.cur_tok.ID)
+		return this.SyntaxError(msg)
+	}
+	pattern := this.cur_tok.Literal
+
+	this.readToken()
+	if this.cur_tok.ID != token.SEMICOLON {
+		msg := fmt.Sprintf("expected ';' instead found '%s'", this.cur_tok.Literal)
+		return this.SyntaxError(msg)
+	}
+
+	filenames, err := filepath.Glob(pattern)
+	if err != nil {
+		return err
+	}
+	old_tokenizer := this.tokenizer
+	for _, filename := range filenames {
+		reader, err := os.Open(filename)
+		if err != nil {
+			return err
+		}
+		this.cur_section.AddInclude(filename)
+		this.tokenizer = token.NewTokenizer(reader)
+		this.Parse()
+	}
+	fmt.Println(this.cur_section.Includes)
+	this.tokenizer = old_tokenizer
+	this.readToken()
+	return nil
+}
+
 func (this *Parser) parseSection(name string) error {
 	section := config.NewNamedSection(name)
 	this.cur_section.Set(name, section)
@@ -215,6 +249,8 @@ func (this *Parser) Parse() error {
 		switch tok.ID {
 		case token.COMMENT:
 			this.cur_section.AddComment(tok.Literal)
+		case token.INCLUDE:
+			this.parseInclude()
 		case token.IDENTIFIER:
 			if this.cur_tok.ID == token.LBRACKET {
 				err := this.parseSection(tok.Literal)

token/tokenid.go

@@ -19,6 +19,7 @@ const (
 	STRING
 	NULL
 	COMMENT
+	INCLUDE
 )
 
 var tokenNames = [...]string{
@@ -36,6 +37,7 @@ var tokenNames = [...]string{
 	STRING:     "STRING",
 	NULL:       "NULL",
 	COMMENT:    "COMMENT",
+	INCLUDE:    "INCLUDE",
 }
 
 func (this TokenID) String() string {

token/tokenizer.go

@@ -29,6 +29,10 @@ func isNull(str string) bool {
 	return strings.ToLower(str) == "null"
 }
 
+func isInclude(str string) bool {
+	return strings.ToLower(str) == "include"
+}
+
 type Tokenizer struct {
 	cur_line int
 	cur_col  int
@@ -86,6 +90,8 @@ func (this *Tokenizer) parseIdentifier() {
 		this.cur_tok.ID = BOOLEAN
 	} else if isNull(this.cur_tok.Literal) {
 		this.cur_tok.ID = NULL
+	} else if isInclude(this.cur_tok.Literal) {
+		this.cur_tok.ID = INCLUDE
 	}
 }