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-rw-r--r--src/lib/Make.deps1
-rw-r--r--src/lib/Makefile2
-rw-r--r--src/lib/format/Makefile76
-rw-r--r--src/lib/format/format.go786
-rw-r--r--src/lib/format/format_test.go365
-rw-r--r--src/lib/format/parser.go445
6 files changed, 1675 insertions, 0 deletions
diff --git a/src/lib/Make.deps b/src/lib/Make.deps
index 6a965e327..4a1805f4c 100644
--- a/src/lib/Make.deps
+++ b/src/lib/Make.deps
@@ -10,6 +10,7 @@ exec.install: os.install strings.install
exvar.install: fmt.install http.install io.install log.install strconv.install sync.install
flag.install: fmt.install os.install strconv.install
fmt.install: io.install os.install reflect.install strconv.install utf8.install
+format.install: container/vector.install flag.install fmt.install go/scanner.install go/token.install io.install os.install reflect.install runtime.install strconv.install strings.install
go/ast.install: go/token.install unicode.install utf8.install
go/doc.install: container/vector.install fmt.install go/ast.install go/token.install io.install once.install regexp.install sort.install strings.install template.install
go/parser.install: container/vector.install fmt.install go/ast.install go/scanner.install go/token.install io.install os.install
diff --git a/src/lib/Makefile b/src/lib/Makefile
index 8aa70cd47..d0658605e 100644
--- a/src/lib/Makefile
+++ b/src/lib/Makefile
@@ -26,6 +26,7 @@ DIRS=\
exvar\
flag\
fmt\
+ format\
go/ast\
go/doc\
go/parser\
@@ -73,6 +74,7 @@ TEST=\
exvar\
flag\
fmt\
+ format\
go/parser\
go/scanner\
hash/adler32\
diff --git a/src/lib/format/Makefile b/src/lib/format/Makefile
new file mode 100644
index 000000000..597933241
--- /dev/null
+++ b/src/lib/format/Makefile
@@ -0,0 +1,76 @@
+# Copyright 2009 The Go Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style
+# license that can be found in the LICENSE file.
+
+# DO NOT EDIT. Automatically generated by gobuild.
+# gobuild -m >Makefile
+
+D=
+
+O_arm=5
+O_amd64=6
+O_386=8
+OS=568vq
+
+O=$(O_$(GOARCH))
+GC=$(O)g -I_obj
+CC=$(O)c -FVw
+AS=$(O)a
+AR=6ar
+
+default: packages
+
+clean:
+ rm -rf *.[$(OS)] *.a [$(OS)].out _obj
+
+test: packages
+ gotest
+
+coverage: packages
+ gotest
+ 6cov -g `pwd` | grep -v '_test\.go:'
+
+%.$O: %.go
+ $(GC) $*.go
+
+%.$O: %.c
+ $(CC) $*.c
+
+%.$O: %.s
+ $(AS) $*.s
+
+O1=\
+ format.$O\
+
+O2=\
+ parser.$O\
+
+
+phases: a1 a2
+_obj$D/format.a: phases
+
+a1: $(O1)
+ $(AR) grc _obj$D/format.a format.$O
+ rm -f $(O1)
+
+a2: $(O2)
+ $(AR) grc _obj$D/format.a parser.$O
+ rm -f $(O2)
+
+
+newpkg: clean
+ mkdir -p _obj$D
+ $(AR) grc _obj$D/format.a
+
+$(O1): newpkg
+$(O2): a1
+$(O3): a2
+
+nuke: clean
+ rm -f $(GOROOT)/pkg$D/format.a
+
+packages: _obj$D/format.a
+
+install: packages
+ test -d $(GOROOT)/pkg && mkdir -p $(GOROOT)/pkg$D
+ cp _obj$D/format.a $(GOROOT)/pkg$D/format.a
diff --git a/src/lib/format/format.go b/src/lib/format/format.go
new file mode 100644
index 000000000..392a9d0f0
--- /dev/null
+++ b/src/lib/format/format.go
@@ -0,0 +1,786 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/* The format package implements syntax-directed, type-driven formatting
+ of arbitrary data structures. Formatting a data structure consists of
+ two phases: first, a parser reads a format specification and builds a
+ "compiled" format. Then, the format can be applied repeatedly to
+ arbitrary values. Applying a format to a value evaluates to a []byte
+ containing the formatted value bytes, or nil.
+
+ A format specification is a set of package declarations and format rules:
+
+ Format = [ Entry { ";" Entry } [ ";" ] ] .
+ Entry = PackageDecl | FormatRule .
+
+ (The syntax of a format specification is presented in the same EBNF
+ notation as used in the Go language specification. The syntax of white
+ space, comments, identifiers, and string literals is the same as in Go.)
+
+ A package declaration binds a package name (such as 'ast') to a
+ package import path (such as '"go/ast"'). Each package used (in
+ a type name, see below) must be declared once before use.
+
+ PackageDecl = PackageName ImportPath .
+ PackageName = identifier .
+ ImportPath = string .
+
+ A format rule binds a rule name to a format expression. A rule name
+ may be a type name or one of the special names 'default' or '/'.
+ A type name may be the name of a predeclared type (for example, 'int',
+ 'float32', etc.), the package-qualified name of a user-defined type
+ (for example, 'ast.MapType'), or an identifier indicating the structure
+ of unnamed composite types ('array', 'chan', 'func', 'interface', 'map',
+ or 'ptr'). Each rule must have a unique name; rules can be declared in
+ any order.
+
+ FormatRule = RuleName "=" Expression .
+ RuleName = TypeName | "default" | "/" .
+ TypeName = [ PackageName "." ] identifier .
+
+ To format a value, the value's type name is used to select the format rule
+ (there is an override mechanism, see below). The format expression of the
+ selected rule specifies how the value is formatted. Each format expression,
+ when applied to a value, evaluates to a byte sequence or nil.
+
+ In its most general form, a format expression is a list of alternatives,
+ each of which is a sequence of operands:
+
+ Expression = [ Sequence ] { "|" [ Sequence ] } .
+ Sequence = Operand { Operand } .
+
+ The formatted result produced by an expression is the result of the first
+ alternative sequence that evaluates to a non-nil result; if there is no
+ such alternative, the expression evaluates to nil. The result produced by
+ an operand sequence is the concatenation of the results of its operands.
+ If any operand in the sequence evaluates to nil, the entire sequence
+ evaluates to nil.
+
+ There are five kinds of operands:
+
+ Operand = Literal | Field | Group | Option | Repetition .
+
+ Literals evaluate to themselves, with two substitutions. First,
+ %-formats expand in the manner of fmt.Printf, with the current value
+ passed as the parameter. Second, the current indentation (see below)
+ is inserted after every newline character.
+
+ Literal = string .
+
+ This table shows string literals applied to the value 42 and the
+ corresponding formatted result:
+
+ "foo" foo
+ "%x" 2a
+ "x = %d" x = 42
+ "%#x = %d" 0x2a = 42
+
+ A field operand is a field name optionally followed by an alternate
+ rule name. The field name may be an identifier or one of the special
+ names ^ or *.
+
+ Field = FieldName [ ":" RuleName ] .
+ FieldName = identifier | "^" | "*" .
+
+ If the field name is an identifier, the current value must be a struct,
+ and there must be a field with that name in the struct. The same lookup
+ rules apply as in the Go language (for instance, the name of an anonymous
+ field is the unqualified type name). The field name denotes the field
+ value in the struct. If the field is not found, formatting is aborted
+ and an error message is returned. (TODO consider changing the semantics
+ such that if a field is not found, it evaluates to nil).
+
+ The special name '^' denotes the current value. (TODO see if ^ can
+ change to @ or be eliminated).
+
+ The meaning of the special name '*' depends on the type of the current
+ value:
+
+ array, slice types array, slice element (inside {} only, see below)
+ interfaces value stored in interface
+ pointers value pointed to by pointer
+
+ (Implementation restriction: channel, function and map types are not
+ supported due to missing reflection support).
+
+ Fields are evaluated as follows: If the field value is nil, or an array
+ or slice element does not exist, the result is nil (see below for details
+ on array/slice elements). If the value is not nil the field value is
+ formatted (recursively) using the rule corresponding to its type name,
+ or the alternate rule name, if given.
+
+ The following example shows a complete format specification for a
+ struct 'myPackage.Point'. Assume the package
+
+ package myPackage // in directory myDir/myPackage
+ type Point struct {
+ name string;
+ x, y int;
+ }
+
+ Applying the format specification
+
+ myPackage "myDir/myPackage";
+ int = "%d";
+ hexInt = "0x%x";
+ string = "---%s---";
+ myPackage.Point = name "{" x ", " y:hexInt "}";
+
+ to the value myPackage.Point{"foo", 3, 15} results in
+
+ ---foo---{3, 0xf}
+
+ Finally, an operand may be a grouped, optional, or repeated expression.
+ A grouped expression ("group") groups a more complex expression (body)
+ so that it can be used in place of a single operand:
+
+ Group = "(" [ Indentation ">>" ] Body ")" .
+ Indentation = Expression .
+ Body = Expression .
+
+ A group body may be prefixed by an indentation expression followed by '>>'.
+ The indentation expression is applied to the current value like any other
+ expression and the result, if not nil, is appended to the current indentation
+ during the evaluation of the body (see also formatting state, below).
+
+ An optional expression ("option") is enclosed in '[]' brackets.
+
+ Option = "[" Body "]" .
+
+ An option evaluates to its body, except that if the body evaluates to nil,
+ the option expression evaluates to an empty []byte. Thus an option's purpose
+ is to protect the expression containing the option from a nil operand.
+
+ A repeated expression ("repetition") is enclosed in '{}' braces.
+
+ Repetition = "{" Body [ "/" Separator ] "}" .
+ Separator = Expression .
+
+ A repeated expression is evaluated as follows: The body is evaluated
+ repeatedly and its results are concatenated until the body evaluates
+ to nil. The result of the repetition is the (possibly empty) concatenation,
+ but it is never nil. An implicit index is supplied for the evaluation of
+ the body: that index is used to address elements of arrays or slices. If
+ the corresponding elements do not exist, the field denoting the element
+ evaluates to nil (which in turn may terminate the repetition).
+
+ The body of a repetition may be followed by a '/' and a "separator"
+ expression. If the separator is present, it is invoked between repetitions
+ of the body.
+
+ The following example shows a complete format specification for formatting
+ a slice of unnamed type. Applying the specification
+
+ int = "%b";
+ array = { * / ", " }; // array is the type name for an unnamed slice
+
+ to the value '[]int{2, 3, 5, 7}' results in
+
+ 10, 11, 101, 111
+
+ Default rule: If a format rule named 'default' is present, it is used for
+ formatting a value if no other rule was found. A common default rule is
+
+ default = "%v"
+
+ to provide default formatting for basic types without having to specify
+ a specific rule for each basic type.
+
+ Global separator rule: If a format rule named '/' is present, it is
+ invoked with the current value between literals. If the separator
+ expression evaluates to nil, it is ignored.
+
+ For instance, a global separator rule may be used to punctuate a sequence
+ of values with commas. The rules:
+
+ default = "%v";
+ / = ", ";
+
+ will format an argument list by printing each one in its default format,
+ separated by a comma and a space.
+*/
+package format
+
+import (
+ "container/vector";
+ "fmt";
+ "go/token";
+ "io";
+ "os";
+ "reflect";
+ "runtime";
+ "strconv";
+ "strings";
+)
+
+
+// ----------------------------------------------------------------------------
+// Format representation
+
+type State struct
+
+// Custom formatters implement the Formatter function type.
+// A formatter is invoked with the current formatting state, the
+// value to format, and the rule name under which the formatter
+// was installed (the same formatter function may be installed
+// under different names). The formatter may access the current state
+// to guide formatting and use State.Write to append to the state's
+// output.
+//
+// A formatter must return a boolean value indicating if it evaluated
+// to a non-nil value (true), or a nil value (false).
+//
+type Formatter func(state *State, value interface{}, ruleName string) bool
+
+
+// A FormatterMap is a set of custom formatters.
+// It maps a rule name to a formatter function.
+//
+type FormatterMap map [string] Formatter;
+
+
+// A parsed format expression is built from the following nodes.
+//
+type (
+ expr interface {};
+
+ alternatives []expr; // x | y | z
+
+ sequence []expr; // x y z
+
+ literal [][]byte; // a list of string segments, possibly starting with '%'
+
+ field struct {
+ fieldName string; // including "^", "*"
+ ruleName string; // "" if no rule name specified
+ };
+
+ group struct {
+ indent, body expr; // (indent >> body)
+ };
+
+ option struct {
+ body expr; // [body]
+ };
+
+ repetition struct {
+ body, separator expr; // {body / separator}
+ };
+
+ custom struct {
+ ruleName string;
+ fun Formatter
+ };
+)
+
+
+// A Format is the result of parsing a format specification.
+// The format may be applied repeatedly to format values.
+//
+type Format map [string] expr;
+
+
+// ----------------------------------------------------------------------------
+// Formatting
+
+// An application-specific environment may be provided to Format.Apply;
+// the environment is available inside custom formatters via State.Env().
+// Environments must implement copying; the Copy method must return an
+// complete copy of the receiver. This is necessary so that the formatter
+// can save and restore an environment (in case of an absent expression).
+//
+// If the Environment doesn't change during formatting (this is under
+// control of the custom formatters), the Copy function can simply return
+// the receiver, and thus can be very light-weight.
+//
+type Environment interface {
+ Copy() Environment
+}
+
+
+// State represents the current formatting state.
+// It is provided as argument to custom formatters.
+//
+type State struct {
+ fmt Format; // format in use
+ env Environment; // user-supplied environment
+ errors chan os.Error; // not chan *Error (errors <- nil would be wrong!)
+ hasOutput bool; // true after the first literal has been written
+ indent io.ByteBuffer; // current indentation
+ output io.ByteBuffer; // format output
+ linePos token.Position; // position of line beginning (Column == 0)
+ default_ expr; // possibly nil
+ separator expr; // possibly nil
+}
+
+
+func newState(fmt Format, env Environment, errors chan os.Error) *State {
+ s := new(State);
+ s.fmt = fmt;
+ s.env = env;
+ s.errors = errors;
+ s.linePos = token.Position{Line: 1};
+
+ // if we have a default rule, cache it's expression for fast access
+ if x, found := fmt["default"]; found {
+ s.default_ = x;
+ }
+
+ // if we have a global separator rule, cache it's expression for fast access
+ if x, found := fmt["/"]; found {
+ s.separator = x;
+ }
+
+ return s;
+}
+
+
+// Env returns the environment passed to Format.Apply.
+func (s *State) Env() interface{} {
+ return s.env;
+}
+
+
+// LinePos returns the position of the current line beginning
+// in the state's output buffer. Line numbers start at 1.
+//
+func (s *State) LinePos() token.Position {
+ return s.linePos;
+}
+
+
+// Pos returns the position of the next byte to be written to the
+// output buffer. Line numbers start at 1.
+//
+func (s *State) Pos() token.Position {
+ offs := s.output.Len();
+ return token.Position{Line: s.linePos.Line, Column: offs - s.linePos.Offset, Offset: offs};
+}
+
+
+// Write writes data to the output buffer, inserting the indentation
+// string after each newline. It cannot return an error.
+//
+func (s *State) Write(data []byte) (int, os.Error) {
+ n := 0;
+ i0 := 0;
+ for i, ch := range data {
+ if ch == '\n' {
+ // write text segment and indentation
+ n1, _ := s.output.Write(data[i0 : i+1]);
+ n2, _ := s.output.Write(s.indent.Data());
+ n += n1 + n2;
+ i0 = i + 1;
+ s.linePos.Offset = s.output.Len();
+ s.linePos.Line++;
+ }
+ }
+ n3, _ := s.output.Write(data[i0 : len(data)]);
+ return n + n3, nil;
+}
+
+
+type checkpoint struct {
+ env Environment;
+ hasOutput bool;
+ outputLen int;
+ linePos token.Position;
+}
+
+
+func (s *State) save() checkpoint {
+ saved := checkpoint{nil, s.hasOutput, s.output.Len(), s.linePos};
+ if s.env != nil {
+ saved.env = s.env.Copy();
+ }
+ return saved;
+}
+
+
+func (s *State) restore(m checkpoint) {
+ s.env = m.env;
+ s.output.Truncate(m.outputLen);
+}
+
+
+func (s *State) error(msg string) {
+ s.errors <- os.NewError(msg);
+ runtime.Goexit();
+}
+
+
+// getField searches in val, which must be a struct, for a field
+// with the given name. It returns the value and the embedded depth
+// where it was found.
+//
+func getField(val reflect.Value, fieldname string) (reflect.Value, int) {
+ // do we have a struct in the first place?
+ if val.Kind() != reflect.StructKind {
+ return nil, 0;
+ }
+
+ sval, styp := val.(reflect.StructValue), val.Type().(reflect.StructType);
+
+ // look for field at the top level
+ for i := 0; i < styp.Len(); i++ {
+ name, typ, tag, offset := styp.Field(i);
+ if name == fieldname || name == "" && strings.HasSuffix(typ.Name(), "." + fieldname) /* anonymous field */ {
+ return sval.Field(i), 0;
+ }
+ }
+
+ // look for field in anonymous fields
+ var field reflect.Value;
+ level := 1000; // infinity (no struct has that many levels)
+ for i := 0; i < styp.Len(); i++ {
+ name, typ, tag, offset := styp.Field(i);
+ if name == "" {
+ f, l := getField(sval.Field(i), fieldname);
+ // keep the most shallow field
+ if f != nil {
+ switch {
+ case l < level:
+ field, level = f, l;
+ case l == level:
+ // more than one field at the same level,
+ // possibly an error unless there is a more
+ // shallow field found later
+ field = nil;
+ }
+ }
+ }
+ }
+
+ return field, level + 1;
+}
+
+
+// TODO At the moment, unnamed types are simply mapped to the default
+// names below. For instance, all unnamed arrays are mapped to
+// 'array' which is not really sufficient. Eventually one may want
+// to be able to specify rules for say an unnamed slice of T.
+//
+var defaultNames = map[int]string {
+ reflect.ArrayKind: "array",
+ reflect.BoolKind: "bool",
+ reflect.ChanKind: "chan",
+ reflect.DotDotDotKind: "ellipsis",
+ reflect.FloatKind: "float",
+ reflect.Float32Kind: "float32",
+ reflect.Float64Kind: "float64",
+ reflect.FuncKind: "func",
+ reflect.IntKind: "int",
+ reflect.Int16Kind: "int16",
+ reflect.Int32Kind: "int32",
+ reflect.Int64Kind: "int64",
+ reflect.Int8Kind: "int8",
+ reflect.InterfaceKind: "interface",
+ reflect.MapKind: "map",
+ reflect.PtrKind: "ptr",
+ reflect.StringKind: "string",
+ reflect.StructKind: "struct",
+ reflect.UintKind: "uint",
+ reflect.Uint16Kind: "uint16",
+ reflect.Uint32Kind: "uint32",
+ reflect.Uint64Kind: "uint64",
+ reflect.Uint8Kind: "uint8",
+ reflect.UintptrKind: "uintptr",
+}
+
+
+func typename(value reflect.Value) string {
+ name := value.Type().Name();
+ if name == "" {
+ if defaultName, found := defaultNames[value.Kind()]; found {
+ name = defaultName;
+ }
+ }
+ return name;
+}
+
+
+func (s *State) getFormat(name string) expr {
+ if fexpr, found := s.fmt[name]; found {
+ return fexpr;
+ }
+
+ if s.default_ != nil {
+ return s.default_;
+ }
+
+ s.error(fmt.Sprintf("no format rule for type: '%s'", name));
+ return nil;
+}
+
+
+// eval applies a format expression fexpr to a value. If the expression
+// evaluates internally to a non-nil []byte, that slice is appended to
+// the state's output buffer and eval returns true. Otherwise, eval
+// returns false and the state remains unchanged.
+//
+func (s *State) eval(fexpr expr, value reflect.Value, index int) bool {
+ // an empty format expression always evaluates
+ // to a non-nil (but empty) []byte
+ if fexpr == nil {
+ return true;
+ }
+
+ switch t := fexpr.(type) {
+ case alternatives:
+ // append the result of the first alternative that evaluates to
+ // a non-nil []byte to the state's output
+ mark := s.save();
+ for _, x := range t {
+ if s.eval(x, value, index) {
+ return true;
+ }
+ s.restore(mark);
+ }
+ return false;
+
+ case sequence:
+ // append the result of all operands to the state's output
+ // unless a nil result is encountered
+ mark := s.save();
+ for _, x := range t {
+ if !s.eval(x, value, index) {
+ s.restore(mark);
+ return false;
+ }
+ }
+ return true;
+
+ case literal:
+ // write separator, if any
+ if s.hasOutput {
+ // not the first literal
+ if s.separator != nil {
+ sep := s.separator; // save current separator
+ s.separator = nil; // and disable it (avoid recursion)
+ mark := s.save();
+ if !s.eval(sep, value, index) {
+ s.restore(mark);
+ }
+ s.separator = sep; // enable it again
+ }
+ }
+ s.hasOutput = true;
+ // write literal segments
+ for _, lit := range t {
+ if lit[0] == '%' && len(lit) > 1 {
+ // segment contains a %-format at the beginning
+ if lit[1] == '%' {
+ // "%%" is printed as a single "%"
+ s.Write(lit[1 : len(lit)]);
+ } else {
+ // use s instead of s.output to get indentation right
+ fmt.Fprintf(s, string(lit), value.Interface());
+ }
+ } else {
+ // segment contains no %-formats
+ s.Write(lit);
+ }
+ }
+ return true; // a literal never evaluates to nil
+
+ case *field:
+ // determine field value
+ switch t.fieldName {
+ case "^":
+ // field value is current value
+
+ case "*":
+ // indirection: operation is type-specific
+ switch v := value.(type) {
+ case reflect.ArrayValue:
+ if v.IsNil() || v.Len() <= index {
+ return false;
+ }
+ value = v.Elem(index);
+
+ case reflect.MapValue:
+ s.error("reflection support for maps incomplete");
+
+ case reflect.PtrValue:
+ if v.IsNil() {
+ return false;
+ }
+ value = v.Sub();
+
+ case reflect.InterfaceValue:
+ if v.IsNil() {
+ return false;
+ }
+ value = v.Value();
+
+ case reflect.ChanValue:
+ s.error("reflection support for chans incomplete");
+
+ case reflect.FuncValue:
+ s.error("reflection support for funcs incomplete");
+
+ default:
+ s.error(fmt.Sprintf("error: * does not apply to `%s`", value.Type().Name()));
+ }
+
+ default:
+ // value is value of named field
+ field, _ := getField(value, t.fieldName);
+ if field == nil {
+ // TODO consider just returning false in this case
+ s.error(fmt.Sprintf("error: no field `%s` in `%s`", t.fieldName, value.Type().Name()));
+ }
+ value = field;
+ }
+
+ // determine rule
+ ruleName := t.ruleName;
+ if ruleName == "" {
+ // no alternate rule name, value type determines rule
+ ruleName = typename(value)
+ }
+ fexpr = s.getFormat(ruleName);
+
+ mark := s.save();
+ if !s.eval(fexpr, value, index) {
+ s.restore(mark);
+ return false;
+ }
+ return true;
+
+ case *group:
+ // remember current indentation
+ indentLen := s.indent.Len();
+
+ // update current indentation
+ mark := s.save();
+ s.eval(t.indent, value, index);
+ // if the indentation evaluates to nil, the state's output buffer
+ // didn't change - either way it's ok to append the difference to
+ // the current identation
+ s.indent.Write(s.output.Data()[mark.outputLen : s.output.Len()]);
+ s.restore(mark);
+
+ // format group body
+ mark = s.save();
+ b := true;
+ if !s.eval(t.body, value, index) {
+ s.restore(mark);
+ b = false;
+ }
+
+ // reset indentation
+ s.indent.Truncate(indentLen);
+ return b;
+
+ case *option:
+ // evaluate the body and append the result to the state's output
+ // buffer unless the result is nil
+ mark := s.save();
+ if !s.eval(t.body, value, 0) { // TODO is 0 index correct?
+ s.restore(mark);
+ }
+ return true; // an option never evaluates to nil
+
+ case *repetition:
+ // evaluate the body and append the result to the state's output
+ // buffer until a result is nil
+ for i := 0; ; i++ {
+ mark := s.save();
+ // write separator, if any
+ if i > 0 && t.separator != nil {
+ // nil result from separator is ignored
+ mark := s.save();
+ if !s.eval(t.separator, value, i) {
+ s.restore(mark);
+ }
+ }
+ if !s.eval(t.body, value, i) {
+ s.restore(mark);
+ break;
+ }
+ }
+ return true; // a repetition never evaluates to nil
+
+ case *custom:
+ // invoke the custom formatter to obtain the result
+ mark := s.save();
+ if !t.fun(s, value.Interface(), t.ruleName) {
+ s.restore(mark);
+ return false;
+ }
+ return true;
+ }
+
+ panic("unreachable");
+ return false;
+}
+
+
+// Eval formats each argument according to the format
+// f and returns the resulting []byte and os.Error. If
+// an error occured, the []byte contains the partially
+// formatted result. An environment env may be passed
+// in which is available in custom formatters through
+// the state parameter.
+//
+func (f Format) Eval(env Environment, args ...) ([]byte, os.Error) {
+ errors := make(chan os.Error);
+ s := newState(f, env, errors);
+
+ go func() {
+ value := reflect.NewValue(args).(reflect.StructValue);
+ for i := 0; i < value.Len(); i++ {
+ fld := value.Field(i);
+ mark := s.save();
+ if !s.eval(s.getFormat(typename(fld)), fld, 0) { // TODO is 0 index correct?
+ s.restore(mark);
+ }
+ }
+ errors <- nil; // no errors
+ }();
+
+ return s.output.Data(), <- errors;
+}
+
+
+// ----------------------------------------------------------------------------
+// Convenience functions
+
+// Fprint formats each argument according to the format f
+// and writes to w. The result is the total number of bytes
+// written and an os.Error, if any.
+//
+func (f Format) Fprint(w io.Writer, env Environment, args ...) (int, os.Error) {
+ data, err := f.Eval(env, args);
+ if err != nil {
+ // TODO should we print partial result in case of error?
+ return 0, err;
+ }
+ return w.Write(data);
+}
+
+
+// Print formats each argument according to the format f
+// and writes to standard output. The result is the total
+// number of bytes written and an os.Error, if any.
+//
+func (f Format) Print(args ...) (int, os.Error) {
+ return f.Fprint(os.Stdout, nil, args);
+}
+
+
+// Sprint formats each argument according to the format f
+// and returns the resulting string. If an error occurs
+// during formatting, the result string contains the
+// partially formatted result followed by an error message.
+//
+func (f Format) Sprint(args ...) string {
+ var buf io.ByteBuffer;
+ n, err := f.Fprint(&buf, nil, args);
+ if err != nil {
+ fmt.Fprintf(&buf, "--- Sprint(%s) failed: %v", fmt.Sprint(args), err);
+ }
+ return string(buf.Data());
+}
diff --git a/src/lib/format/format_test.go b/src/lib/format/format_test.go
new file mode 100644
index 000000000..92e0d0ea5
--- /dev/null
+++ b/src/lib/format/format_test.go
@@ -0,0 +1,365 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package format
+
+import (
+ "fmt";
+ "format";
+ "io";
+ "os";
+ "testing";
+)
+
+
+func parse(t *testing.T, form string, fmap format.FormatterMap) format.Format {
+ f, err := format.Parse(io.StringBytes(form), fmap);
+ if err != nil {
+ t.Errorf("Parse(%s): %v", err);
+ return nil;
+ }
+ return f;
+}
+
+
+func verify(t *testing.T, f format.Format, expected string, args ...) {
+ if f == nil {
+ return; // allow other tests to run
+ }
+ result := f.Sprint(args);
+ if result != expected {
+ t.Errorf(
+ "result : `%s`\nexpected: `%s`\n\n",
+ result, expected
+ )
+ }
+}
+
+
+func formatter(s *format.State, value interface{}, rule_name string) bool {
+ switch rule_name {
+ case "/":
+ fmt.Fprintf(s, "%d %d %d", s.Pos().Line, s.LinePos().Column, s.Pos().Column);
+ return true;
+ case "blank":
+ s.Write([]byte{' '});
+ return true;
+ case "int":
+ if value.(int) & 1 == 0 {
+ fmt.Fprint(s, "even ");
+ } else {
+ fmt.Fprint(s, "odd ");
+ }
+ return true;
+ case "nil":
+ return false;
+ }
+ panic("unreachable");
+ return false;
+}
+
+
+func TestCustomFormatters(t *testing.T) {
+ fmap0 := format.FormatterMap{ "/": formatter };
+ fmap1 := format.FormatterMap{ "int": formatter, "blank": formatter, "nil": formatter };
+
+ f := parse(t, `int=`, fmap0);
+ verify(t, f, ``, 1, 2, 3);
+
+ f = parse(t, `int="#"`, nil);
+ verify(t, f, `###`, 1, 2, 3);
+
+ f = parse(t, `int="#";string="%s"`, fmap0);
+ verify(t, f, "#1 0 1#1 0 7#1 0 13\n2 0 0foo2 0 8\n", 1, 2, 3, "\n", "foo", "\n");
+
+ f = parse(t, ``, fmap1);
+ verify(t, f, `even odd even odd `, 0, 1, 2, 3);
+
+ f = parse(t, `/ =^:blank; float="#"`, fmap1);
+ verify(t, f, `# # #`, 0.0, 1.0, 2.0);
+
+ f = parse(t, `float=^:nil`, fmap1);
+ verify(t, f, ``, 0.0, 1.0, 2.0);
+
+ // TODO needs more tests
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting of basic and simple composite types
+
+func check(t *testing.T, form, expected string, args ...) {
+ f := parse(t, form, nil);
+ result := f.Sprint(args);
+ if result != expected {
+ t.Errorf(
+ "format : %s\nresult : `%s`\nexpected: `%s`\n\n",
+ form, result, expected
+ )
+ }
+}
+
+
+func TestBasicTypes(t *testing.T) {
+ check(t, ``, ``);
+ check(t, `bool=":%v"`, `:true:false`, true, false);
+ check(t, `int="%b %d %o 0x%x"`, `101010 42 52 0x2a`, 42);
+
+ check(t, `int="%"`, `%`, 42);
+ check(t, `int="%%"`, `%`, 42);
+ check(t, `int="**%%**"`, `**%**`, 42);
+ check(t, `int="%%%%%%"`, `%%%`, 42);
+ check(t, `int="%%%d%%"`, `%42%`, 42);
+
+ const i = -42;
+ const is = `-42`;
+ check(t, `int ="%d"`, is, i);
+ check(t, `int8 ="%d"`, is, int8(i));
+ check(t, `int16="%d"`, is, int16(i));
+ check(t, `int32="%d"`, is, int32(i));
+ check(t, `int64="%d"`, is, int64(i));
+
+ const u = 42;
+ const us = `42`;
+ check(t, `uint ="%d"`, us, uint(u));
+ check(t, `uint8 ="%d"`, us, uint8(u));
+ check(t, `uint16="%d"`, us, uint16(u));
+ check(t, `uint32="%d"`, us, uint32(u));
+ check(t, `uint64="%d"`, us, uint64(u));
+
+ const f = 3.141592;
+ const fs = `3.141592`;
+ check(t, `float ="%g"`, fs, f);
+ check(t, `float32="%g"`, fs, float32(f));
+ check(t, `float64="%g"`, fs, float64(f));
+}
+
+
+func TestArrayTypes(t *testing.T) {
+ var a0 [10]int;
+ check(t, `array="array";`, `array`, a0);
+
+ a1 := [...]int{1, 2, 3};
+ check(t, `array="array";`, `array`, a1);
+ check(t, `array={*}; int="%d";`, `123`, a1);
+ check(t, `array={* / ", "}; int="%d";`, `1, 2, 3`, a1);
+ check(t, `array={* / *}; int="%d";`, `12233`, a1);
+
+ a2 := []interface{}{42, "foo", 3.14};
+ check(t, `array={* / ", "}; interface=*; string="bar"; default="%v";`, `42, bar, 3.14`, a2);
+}
+
+
+func TestChanTypes(t *testing.T) {
+ var c0 chan int;
+ check(t, `chan="chan"`, `chan`, c0);
+
+ c1 := make(chan int);
+ go func(){ c1 <- 42 }();
+ check(t, `chan="chan"`, `chan`, c1);
+ // check(t, `chan=*`, `42`, c1); // reflection support for chans incomplete
+}
+
+
+func TestFuncTypes(t *testing.T) {
+ var f0 func() int;
+ check(t, `func="func"`, `func`, f0);
+
+ f1 := func() int { return 42; };
+ check(t, `func="func"`, `func`, f1);
+ // check(t, `func=*`, `42`, f1); // reflection support for funcs incomplete
+}
+
+
+func TestInterfaceTypes(t *testing.T) {
+ var i0 interface{};
+ check(t, `interface="interface"`, `interface`, i0);
+
+ i0 = "foo";
+ check(t, `interface="interface"`, `interface`, i0);
+ check(t, `interface=*; string="%s"`, `foo`, i0);
+}
+
+
+func TestMapTypes(t *testing.T) {
+ var m0 map[string]int;
+ check(t, `map="map"`, `map`, m0);
+
+ m1 := map[string]int{};
+ check(t, `map="map"`, `map`, m1);
+ // check(t, `map=*`, ``, m1); // reflection support for maps incomplete
+}
+
+
+func TestPointerTypes(t *testing.T) {
+ var p0 *int;
+ check(t, `ptr="ptr"`, `ptr`, p0);
+ check(t, `ptr=*`, ``, p0);
+ check(t, `ptr=*|"nil"`, `nil`, p0);
+
+ x := 99991;
+ p1 := &x;
+ check(t, `ptr="ptr"`, `ptr`, p1);
+ check(t, `ptr=*; int="%d"`, `99991`, p1);
+}
+
+
+func TestDefaultRule(t *testing.T) {
+ check(t, `default="%v"`, `42foo3.14`, 42, "foo", 3.14);
+ check(t, `default="%v"; int="%x"`, `abcdef`, 10, 11, 12, 13, 14, 15);
+ check(t, `default="%v"; int="%x"`, `ab**ef`, 10, 11, "**", 14, 15);
+ check(t, `default="%x"; int=^:default`, `abcdef`, 10, 11, 12, 13, 14, 15);
+}
+
+
+func TestGlobalSeparatorRule(t *testing.T) {
+ check(t, `int="%d"; / ="-"`, `1-2-3-4`, 1, 2, 3, 4);
+ check(t, `int="%x%x"; / ="*"`, `aa*aa`, 10, 10);
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting of a struct
+
+type T1 struct {
+ a int;
+}
+
+const F1 =
+ `format "format";`
+ `int = "%d";`
+ `format.T1 = "<" a ">";`
+
+func TestStruct1(t *testing.T) {
+ check(t, F1, "<42>", T1{42});
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting of a struct with an optional field (ptr)
+
+type T2 struct {
+ s string;
+ p *T1;
+}
+
+const F2a =
+ F1 +
+ `string = "%s";`
+ `ptr = *;`
+ `format.T2 = s ["-" p "-"];`
+
+const F2b =
+ F1 +
+ `string = "%s";`
+ `ptr = *;`
+ `format.T2 = s ("-" p "-" | "empty");`;
+
+func TestStruct2(t *testing.T) {
+ check(t, F2a, "foo", T2{"foo", nil});
+ check(t, F2a, "bar-<17>-", T2{"bar", &T1{17}});
+ check(t, F2b, "fooempty", T2{"foo", nil});
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting of a struct with a repetitive field (slice)
+
+type T3 struct {
+ s string;
+ a []int;
+}
+
+const F3a =
+ `format "format";`
+ `default = "%v";`
+ `array = *;`
+ `format.T3 = s {" " a a / ","};`
+
+const F3b =
+ `format "format";`
+ `int = "%d";`
+ `string = "%s";`
+ `array = *;`
+ `nil = ;`
+ `empty = *:nil;`
+ `format.T3 = s [a:empty ": " {a / "-"}]`
+
+func TestStruct3(t *testing.T) {
+ check(t, F3a, "foo", T3{"foo", nil});
+ check(t, F3a, "foo 00, 11, 22", T3{"foo", []int{0, 1, 2}});
+ check(t, F3b, "bar", T3{"bar", nil});
+ check(t, F3b, "bal: 2-3-5", T3{"bal", []int{2, 3, 5}});
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting of a struct with alternative field
+
+type T4 struct {
+ x *int;
+ a []int;
+}
+
+const F4a =
+ `format "format";`
+ `int = "%d";`
+ `ptr = *;`
+ `array = *;`
+ `nil = ;`
+ `empty = *:nil;`
+ `format.T4 = "<" (x:empty x | "-") ">" `
+
+const F4b =
+ `format "format";`
+ `int = "%d";`
+ `ptr = *;`
+ `array = *;`
+ `nil = ;`
+ `empty = *:nil;`
+ `format.T4 = "<" (a:empty {a / ", "} | "-") ">" `
+
+func TestStruct4(t *testing.T) {
+ x := 7;
+ check(t, F4a, "<->", T4{nil, nil});
+ check(t, F4a, "<7>", T4{&x, nil});
+ check(t, F4b, "<->", T4{nil, nil});
+ check(t, F4b, "<2, 3, 7>", T4{nil, []int{2, 3, 7}});
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting a struct (documentation example)
+
+type Point struct {
+ name string;
+ x, y int;
+}
+
+const FPoint =
+ `format "format";`
+ `int = "%d";`
+ `hexInt = "0x%x";`
+ `string = "---%s---";`
+ `format.Point = name "{" x ", " y:hexInt "}";`
+
+func TestStructPoint(t *testing.T) {
+ p := Point{"foo", 3, 15};
+ check(t, FPoint, "---foo---{3, 0xf}", p);
+}
+
+
+// ----------------------------------------------------------------------------
+// Formatting a slice (documentation example)
+
+const FSlice =
+ `int = "%b";`
+ `array = { * / ", " }`
+
+func TestSlice(t *testing.T) {
+ check(t, FSlice, "10, 11, 101, 111", []int{2, 3, 5, 7});
+}
+
+
+// TODO add more tests
diff --git a/src/lib/format/parser.go b/src/lib/format/parser.go
new file mode 100644
index 000000000..a6e6e5e8e
--- /dev/null
+++ b/src/lib/format/parser.go
@@ -0,0 +1,445 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package format
+
+import (
+ "container/vector";
+ "fmt";
+ "format";
+ "go/scanner";
+ "go/token";
+ "io";
+ "os";
+ "strconv";
+ "strings";
+)
+
+// ----------------------------------------------------------------------------
+// Error handling
+
+// Error describes an individual error. The position Pos, if valid,
+// indicates the format source position the error relates to. The
+// error is specified with the Msg string.
+//
+type Error struct {
+ Pos token.Position;
+ Msg string;
+}
+
+
+func (e *Error) String() string {
+ pos := "";
+ if e.Pos.IsValid() {
+ pos = fmt.Sprintf("%d:%d: ", e.Pos.Line, e.Pos.Column);
+ }
+ return pos + e.Msg;
+}
+
+
+// An ErrorList is a list of errors encountered during parsing.
+type ErrorList []*Error
+
+
+// ErrorList implements SortInterface and the os.Error interface.
+
+func (p ErrorList) Len() int { return len(p); }
+func (p ErrorList) Swap(i, j int) { p[i], p[j] = p[j], p[i]; }
+func (p ErrorList) Less(i, j int) bool { return p[i].Pos.Offset < p[j].Pos.Offset; }
+
+
+func (p ErrorList) String() string {
+ switch len(p) {
+ case 0: return "unspecified error";
+ case 1: return p[0].String();
+ }
+ return fmt.Sprintf("%s (and %d more errors)", p[0].String(), len(p) - 1);
+}
+
+
+// ----------------------------------------------------------------------------
+// Parsing
+
+type parser struct {
+ errors vector.Vector;
+ scanner scanner.Scanner;
+ pos token.Position; // token position
+ tok token.Token; // one token look-ahead
+ lit []byte; // token literal
+
+ packs map [string] string; // PackageName -> ImportPath
+ rules map [string] expr; // RuleName -> Expression
+}
+
+
+func (p *parser) next() {
+ p.pos, p.tok, p.lit = p.scanner.Scan();
+ switch p.tok {
+ case token.CHAN, token.FUNC, token.INTERFACE, token.MAP, token.STRUCT:
+ // Go keywords for composite types are type names
+ // returned by reflect. Accept them as identifiers.
+ p.tok = token.IDENT; // p.lit is already set correctly
+ }
+}
+
+
+func (p *parser) init(src []byte) {
+ p.errors.Init(0);
+ p.scanner.Init(src, p, 0);
+ p.next(); // initializes pos, tok, lit
+ p.packs = make(map [string] string);
+ p.rules = make(map [string] expr);
+}
+
+
+// The parser implements scanner.Error.
+func (p *parser) Error(pos token.Position, msg string) {
+ // Don't collect errors that are on the same line as the previous error
+ // in the hope to reduce the number of spurious errors due to incorrect
+ // parser synchronization.
+ if p.errors.Len() == 0 || p.errors.Last().(*Error).Pos.Line != pos.Line {
+ p.errors.Push(&Error{pos, msg});
+ }
+}
+
+
+func (p *parser) errorExpected(pos token.Position, msg string) {
+ msg = "expected " + msg;
+ if pos.Offset == p.pos.Offset {
+ // the error happened at the current position;
+ // make the error message more specific
+ msg += ", found '" + p.tok.String() + "'";
+ if p.tok.IsLiteral() {
+ msg += " " + string(p.lit);
+ }
+ }
+ p.Error(pos, msg);
+}
+
+
+func (p *parser) expect(tok token.Token) token.Position {
+ pos := p.pos;
+ if p.tok != tok {
+ p.errorExpected(pos, "'" + tok.String() + "'");
+ }
+ p.next(); // make progress in any case
+ return pos;
+}
+
+
+func (p *parser) parseIdentifier() string {
+ name := string(p.lit);
+ p.expect(token.IDENT);
+ return name;
+}
+
+
+func (p *parser) parseTypeName() (string, bool) {
+ pos := p.pos;
+ name, isIdent := p.parseIdentifier(), true;
+ if p.tok == token.PERIOD {
+ // got a package name, lookup package
+ if importPath, found := p.packs[name]; found {
+ name = importPath;
+ } else {
+ p.Error(pos, "package not declared: " + name);
+ }
+ p.next();
+ name, isIdent = name + "." + p.parseIdentifier(), false;
+ }
+ return name, isIdent;
+}
+
+
+// Parses a rule name and returns it. If the rule name is
+// a package-qualified type name, the package name is resolved.
+// The 2nd result value is true iff the rule name consists of a
+// single identifier only (and thus could be a package name).
+//
+func (p *parser) parseRuleName() (string, bool) {
+ name, isIdent := "", false;
+ switch p.tok {
+ case token.IDENT:
+ name, isIdent = p.parseTypeName();
+ case token.DEFAULT:
+ name = "default";
+ p.next();
+ case token.QUO:
+ name = "/";
+ p.next();
+ default:
+ p.errorExpected(p.pos, "rule name");
+ p.next(); // make progress in any case
+ }
+ return name, isIdent;
+}
+
+
+func (p *parser) parseString() string {
+ s := "";
+ if p.tok == token.STRING {
+ var err os.Error;
+ s, err = strconv.Unquote(string(p.lit));
+ // Unquote may fail with an error, but only if the scanner found
+ // an illegal string in the first place. In this case the error
+ // has already been reported.
+ p.next();
+ return s;
+ } else {
+ p.expect(token.STRING);
+ }
+ return s;
+}
+
+
+func (p *parser) parseLiteral() literal {
+ s := io.StringBytes(p.parseString());
+
+ // A string literal may contain %-format specifiers. To simplify
+ // and speed up printing of the literal, split it into segments
+ // that start with "%" possibly followed by a last segment that
+ // starts with some other character.
+ var list vector.Vector;
+ list.Init(0);
+ i0 := 0;
+ for i := 0; i < len(s); i++ {
+ if s[i] == '%' && i+1 < len(s) {
+ // the next segment starts with a % format
+ if i0 < i {
+ // the current segment is not empty, split it off
+ list.Push(s[i0 : i]);
+ i0 = i;
+ }
+ i++; // skip %; let loop skip over char after %
+ }
+ }
+ // the final segment may start with any character
+ // (it is empty iff the string is empty)
+ list.Push(s[i0 : len(s)]);
+
+ // convert list into a literal
+ lit := make(literal, list.Len());
+ for i := 0; i < list.Len(); i++ {
+ lit[i] = list.At(i).([]byte);
+ }
+
+ return lit;
+}
+
+
+func (p *parser) parseField() expr {
+ var fname string;
+ switch p.tok {
+ case token.XOR:
+ fname = "^";
+ p.next();
+ case token.MUL:
+ fname = "*";
+ p.next();
+ case token.IDENT:
+ fname = p.parseIdentifier();
+ default:
+ return nil;
+ }
+
+ var ruleName string;
+ if p.tok == token.COLON {
+ p.next();
+ var _ bool;
+ ruleName, _ = p.parseRuleName();
+ }
+
+ return &field{fname, ruleName};
+}
+
+
+func (p *parser) parseExpression() expr
+
+func (p *parser) parseOperand() (x expr) {
+ switch p.tok {
+ case token.STRING:
+ x = p.parseLiteral();
+
+ case token.LPAREN:
+ p.next();
+ x = p.parseExpression();
+ if p.tok == token.SHR {
+ p.next();
+ x = &group{x, p.parseExpression()};
+ }
+ p.expect(token.RPAREN);
+
+ case token.LBRACK:
+ p.next();
+ x = &option{p.parseExpression()};
+ p.expect(token.RBRACK);
+
+ case token.LBRACE:
+ p.next();
+ x = p.parseExpression();
+ var div expr;
+ if p.tok == token.QUO {
+ p.next();
+ div = p.parseExpression();
+ }
+ x = &repetition{x, div};
+ p.expect(token.RBRACE);
+
+ default:
+ x = p.parseField(); // may be nil
+ }
+
+ return x;
+}
+
+
+func (p *parser) parseSequence() expr {
+ var list vector.Vector;
+ list.Init(0);
+
+ for x := p.parseOperand(); x != nil; x = p.parseOperand() {
+ list.Push(x);
+ }
+
+ // no need for a sequence if list.Len() < 2
+ switch list.Len() {
+ case 0: return nil;
+ case 1: return list.At(0).(expr);
+ }
+
+ // convert list into a sequence
+ seq := make(sequence, list.Len());
+ for i := 0; i < list.Len(); i++ {
+ seq[i] = list.At(i).(expr);
+ }
+ return seq;
+}
+
+
+func (p *parser) parseExpression() expr {
+ var list vector.Vector;
+ list.Init(0);
+
+ for {
+ x := p.parseSequence();
+ if x != nil {
+ list.Push(x);
+ }
+ if p.tok != token.OR {
+ break;
+ }
+ p.next();
+ }
+
+ // no need for an alternatives if list.Len() < 2
+ switch list.Len() {
+ case 0: return nil;
+ case 1: return list.At(0).(expr);
+ }
+
+ // convert list into a alternatives
+ alt := make(alternatives, list.Len());
+ for i := 0; i < list.Len(); i++ {
+ alt[i] = list.At(i).(expr);
+ }
+ return alt;
+}
+
+
+func (p *parser) parseFormat() {
+ for p.tok != token.EOF {
+ pos := p.pos;
+
+ name, isIdent := p.parseRuleName();
+ switch p.tok {
+ case token.STRING:
+ // package declaration
+ importPath := p.parseString();
+
+ // add package declaration
+ if !isIdent {
+ p.Error(pos, "illegal package name: " + name);
+ } else if _, found := p.packs[name]; !found {
+ p.packs[name] = importPath;
+ } else {
+ p.Error(pos, "package already declared: " + name);
+ }
+
+ case token.ASSIGN:
+ // format rule
+ p.next();
+ x := p.parseExpression();
+
+ // add rule
+ if _, found := p.rules[name]; !found {
+ p.rules[name] = x;
+ } else {
+ p.Error(pos, "format rule already declared: " + name);
+ }
+
+ default:
+ p.errorExpected(p.pos, "package declaration or format rule");
+ p.next(); // make progress in any case
+ }
+
+ if p.tok == token.SEMICOLON {
+ p.next();
+ } else {
+ break;
+ }
+ }
+ p.expect(token.EOF);
+}
+
+
+func remap(p *parser, name string) string {
+ i := strings.Index(name, ".");
+ if i >= 0 {
+ packageName := name[0 : i];
+ typeName := name[i : len(name)];
+ // lookup package
+ if importPath, found := p.packs[packageName]; found {
+ name = importPath + "." + typeName;
+ } else {
+ var invalidPos token.Position;
+ p.Error(invalidPos, "package not declared: " + packageName);
+ }
+ }
+ return name;
+}
+
+
+// Parse parses a set of format productions from source src. Custom
+// formatters may be provided via a map of formatter functions. If
+// there are no errors, the result is a Format and the error is nil.
+// Otherwise the format is nil and a non-empty ErrorList is returned.
+//
+func Parse(src []byte, fmap FormatterMap) (Format, os.Error) {
+ // parse source
+ var p parser;
+ p.init(src);
+ p.parseFormat();
+
+ // add custom formatters, if any
+ for name, form := range fmap {
+ name = remap(&p, name);
+ if t, found := p.rules[name]; !found {
+ p.rules[name] = &custom{name, form};
+ } else {
+ var invalidPos token.Position;
+ p.Error(invalidPos, "formatter already declared: " + name);
+ }
+ }
+
+ // convert errors list, if any
+ if p.errors.Len() > 0 {
+ errors := make(ErrorList, p.errors.Len());
+ for i := 0; i < p.errors.Len(); i++ {
+ errors[i] = p.errors.At(i).(*Error);
+ }
+ return nil, errors;
+ }
+
+ return p.rules, nil;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-05-07 18:42:35 +0000