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use std::iter::IntoIterator;
use syntax::ast;
use syntax::codemap::{DUMMY_SP, Span, Spanned, respan};
use syntax::ptr::P;
use invoke::{Invoke, Identity};
use expr::ExprBuilder;
use ident::ToIdent;
use path::PathBuilder;
pub struct PatBuilder<F=Identity> {
callback: F,
span: Span,
}
impl PatBuilder {
pub fn new() -> Self {
PatBuilder::new_with_callback(Identity)
}
}
impl<F> PatBuilder<F>
where F: Invoke<P<ast::Pat>>,
{
pub fn new_with_callback(callback: F) -> Self {
PatBuilder {
callback: callback,
span: DUMMY_SP,
}
}
pub fn span(mut self, span: Span) -> Self {
self.span = span;
self
}
pub fn build(self, pat: P<ast::Pat>) -> F::Result {
self.callback.invoke(pat)
}
pub fn build_pat_(self, pat_: ast::Pat_) -> F::Result {
let span = self.span;
self.build(P(ast::Pat {
id: ast::DUMMY_NODE_ID,
node: pat_,
span: span,
}))
}
pub fn wild(self) -> F::Result {
self.build_pat_(ast::Pat_::PatWild(ast::PatWildKind::PatWildSingle))
}
pub fn wild_multi(self) -> F::Result {
self.build_pat_(ast::Pat_::PatWild(ast::PatWildKind::PatWildMulti))
}
pub fn build_id<I>(self, mode: ast::BindingMode, id: I, sub: Option<P<ast::Pat>>) -> F::Result
where I: ToIdent,
{
let id = respan(self.span, id.to_ident());
self.build_pat_(ast::Pat_::PatIdent(mode, id, sub))
}
pub fn id<I>(self, id: I) -> F::Result
where I: ToIdent
{
let mode = ast::BindingMode::BindByValue(ast::Mutability::MutImmutable);
self.build_id(mode, id, None)
}
pub fn mut_id<I>(self, id: I) -> F::Result
where I: ToIdent
{
let mode = ast::BindingMode::BindByValue(ast::Mutability::MutMutable);
self.build_id(mode, id, None)
}
pub fn ref_id<I>(self, id: I) -> F::Result
where I: ToIdent
{
let mode = ast::BindingMode::BindByRef(ast::Mutability::MutImmutable);
self.build_id(mode, id, None)
}
pub fn ref_mut_id<I>(self, id: I) -> F::Result
where I: ToIdent
{
let mode = ast::BindingMode::BindByRef(ast::Mutability::MutMutable);
self.build_id(mode, id, None)
}
pub fn enum_(self) -> PathBuilder<PatEnumBuilder<F>> {
PathBuilder::new_with_callback(PatEnumBuilder(self))
}
pub fn struct_(self) -> PathBuilder<PatStructBuilder<F>> {
PathBuilder::new_with_callback(PatStructBuilder(self))
}
pub fn expr(self) -> ExprBuilder<PatExprBuilder<F>> {
ExprBuilder::new_with_callback(PatExprBuilder(self))
}
pub fn tuple(self) -> PatTupleBuilder<F> {
PatTupleBuilder {
builder: self,
pats: Vec::new(),
}
}
}
pub struct PatEnumBuilder<F>(PatBuilder<F>);
impl<F> Invoke<ast::Path> for PatEnumBuilder<F> {
type Result = PatEnumPathBuilder<F>;
fn invoke(self, path: ast::Path) -> PatEnumPathBuilder<F> {
PatEnumPathBuilder {
builder: self.0,
path: path,
pats: Vec::new(),
}
}
}
pub struct PatEnumPathBuilder<F> {
builder: PatBuilder<F>,
path: ast::Path,
pats: Vec<P<ast::Pat>>,
}
impl<F> PatEnumPathBuilder<F>
where F: Invoke<P<ast::Pat>>,
{
pub fn with_pats<I>(mut self, iter: I) -> Self
where I: IntoIterator<Item=P<ast::Pat>>,
{
self.pats.extend(iter);
self
}
pub fn pat(self) -> PatBuilder<Self> {
PatBuilder::new_with_callback(self)
}
pub fn with_ids<I, T>(mut self, iter: I) -> Self
where I: IntoIterator<Item=T>,
T: ToIdent,
{
for id in iter {
self = self.id(id);
}
self
}
pub fn id<I>(self, id: I) -> Self
where I: ToIdent
{
self.pat().id(id)
}
pub fn build(self) -> F::Result {
self.builder.build_pat_(ast::Pat_::PatEnum(self.path, Some(self.pats)))
}
}
impl<F> Invoke<P<ast::Pat>> for PatEnumPathBuilder<F>
where F: Invoke<P<ast::Pat>>,
{
type Result = Self;
fn invoke(mut self, pat: P<ast::Pat>) -> Self {
self.pats.push(pat);
self
}
}
pub struct PatStructBuilder<F>(PatBuilder<F>);
impl<F> Invoke<ast::Path> for PatStructBuilder<F> {
type Result = PatStructPathBuilder<F>;
fn invoke(self, path: ast::Path) -> PatStructPathBuilder<F> {
PatStructPathBuilder {
builder: self.0,
path: path,
pats: Vec::new(),
}
}
}
pub struct PatStructPathBuilder<F> {
builder: PatBuilder<F>,
path: ast::Path,
pats: Vec<Spanned<ast::FieldPat>>,
}
impl<F> PatStructPathBuilder<F>
where F: Invoke<P<ast::Pat>>,
{
pub fn with_field_pat(mut self, pat: ast::FieldPat) -> Self {
self.pats.push(respan(self.builder.span, pat));
self
}
pub fn with_pats<I, T>(mut self, iter: I) -> Self
where I: IntoIterator<Item=(T, P<ast::Pat>)>,
T: ToIdent,
{
for (id, pat) in iter {
self = self.pat(id).build(pat);
}
self
}
pub fn pat<I>(self, id: I) -> PatBuilder<PatStructFieldBuilder<F>>
where I: ToIdent,
{
PatBuilder::new_with_callback(PatStructFieldBuilder {
builder: self,
id: id.to_ident(),
})
}
pub fn with_ids<I, T>(mut self, iter: I) -> Self
where I: IntoIterator<Item=T>,
T: ToIdent,
{
for id in iter {
self = self.id(id);
}
self
}
pub fn id<I>(self, id: I) -> Self
where I: ToIdent,
{
let id = id.to_ident();
let span = self.builder.span;
let pat = PatBuilder::new().span(span).id(id);
self.with_field_pat(ast::FieldPat {
ident: id,
pat: pat,
is_shorthand: true,
})
}
pub fn etc(self) -> F::Result {
self.builder.build_pat_(ast::Pat_::PatStruct(self.path, self.pats, true))
}
pub fn build(self) -> F::Result {
self.builder.build_pat_(ast::Pat_::PatStruct(self.path, self.pats, false))
}
}
pub struct PatStructFieldBuilder<F> {
builder: PatStructPathBuilder<F>,
id: ast::Ident,
}
impl<F> Invoke<P<ast::Pat>> for PatStructFieldBuilder<F>
where F: Invoke<P<ast::Pat>>,
{
type Result = PatStructPathBuilder<F>;
fn invoke(self, pat: P<ast::Pat>) -> PatStructPathBuilder<F> {
self.builder.with_field_pat(ast::FieldPat {
ident: self.id,
pat: pat,
is_shorthand: false,
})
}
}
pub struct PatExprBuilder<F>(PatBuilder<F>);
impl<F> Invoke<P<ast::Expr>> for PatExprBuilder<F>
where F: Invoke<P<ast::Pat>>,
{
type Result = F::Result;
fn invoke(self, expr: P<ast::Expr>) -> F::Result {
self.0.build_pat_(ast::Pat_::PatLit(expr))
}
}
pub struct PatTupleBuilder<F> {
builder: PatBuilder<F>,
pats: Vec<P<ast::Pat>>,
}
impl<F: Invoke<P<ast::Pat>>> PatTupleBuilder<F>
where F: Invoke<P<ast::Pat>>
{
pub fn with_pat(mut self, pat: P<ast::Pat>) -> PatTupleBuilder<F> {
self.pats.push(pat);
self
}
pub fn pat(self) -> PatBuilder<PatTupleBuilder<F>> {
PatBuilder::new_with_callback(self)
}
pub fn build(self) -> F::Result {
self.builder.build_pat_(ast::PatTup(self.pats))
}
}
impl<F> Invoke<P<ast::Pat>> for PatTupleBuilder<F>
where F: Invoke<P<ast::Pat>>
{
type Result = PatTupleBuilder<F>;
fn invoke(self, pat: P<ast::Pat>) -> Self {
self.with_pat(pat)
}
}