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| author | Evan Shaw <chickencha@gmail.com> | 2010-04-15 18:04:24 -0700 |
|---|---|---|
| committer | Evan Shaw <chickencha@gmail.com> | 2010-04-15 18:04:24 -0700 |
| commit | 1f7793123a089a8160f948568eedf603c8789829 (patch) | |
| tree | a287824743013ab238ad17f19ac835288416a651 /src | |
| parent | c3b27cb225f3c3aea20283c0c2b693bcc5c4967b (diff) | |
| download | golang-1f7793123a089a8160f948568eedf603c8789829.tar.gz | |
exp/eval: Implement x[lo:]
R=golang-dev, gri
CC=golang-dev
http://codereview.appspot.com/908044
Committer: Robert Griesemer <gri@golang.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/pkg/exp/eval/expr.go | 14 | ||||
| -rw-r--r-- | src/pkg/exp/eval/expr_test.go | 15 |
2 files changed, 23 insertions, 6 deletions
diff --git a/src/pkg/exp/eval/expr.go b/src/pkg/exp/eval/expr.go index 15520830f..8651b0780 100644 --- a/src/pkg/exp/eval/expr.go +++ b/src/pkg/exp/eval/expr.go @@ -589,14 +589,16 @@ func (a *exprCompiler) compile(x ast.Expr, callCtx bool) *expr { return ei.compileIndexExpr(l, r) case *ast.SliceExpr: - end := x.End - if end == nil { - // TODO: set end to len(x.X) - panic("unimplemented") - } + var hi *expr arr := a.compile(x.X, false) lo := a.compile(x.Index, false) - hi := a.compile(end, false) + if x.End == nil { + // End was omitted, so we need to compute len(x.X) + ei := &exprInfo{a.compiler, x.Pos()} + hi = ei.compileBuiltinCallExpr(a.block, lenType, []*expr{arr}) + } else { + hi = a.compile(x.End, false) + } if arr == nil || lo == nil || hi == nil { return nil } diff --git a/src/pkg/exp/eval/expr_test.go b/src/pkg/exp/eval/expr_test.go index 10c7f6be5..f7f367d5e 100644 --- a/src/pkg/exp/eval/expr_test.go +++ b/src/pkg/exp/eval/expr_test.go @@ -85,6 +85,15 @@ var exprTests = []test{ RErr("s[-i]", "negative index"), RErr("s[3]", "index 3 exceeds"), + Val("ai[0:2]", vslice{varray{1, 2}, 2, 2}), + Val("ai[0:1]", vslice{varray{1, 2}, 1, 2}), + Val("ai[0:]", vslice{varray{1, 2}, 2, 2}), + Val("ai[i:]", vslice{varray{2}, 1, 1}), + + Val("sli[0:2]", vslice{varray{1, 2, 3}, 2, 3}), + Val("sli[0:i]", vslice{varray{1, 2, 3}, 1, 3}), + Val("sli[1:]", vslice{varray{2, 3}, 1, 2}), + CErr("1(2)", "cannot call"), CErr("fn(1,2)", "too many"), CErr("fn()", "not enough"), @@ -112,8 +121,14 @@ var exprTests = []test{ Val("len(s)", 3), Val("len(ai)", 2), Val("len(&ai)", 2), + Val("len(ai[0:])", 2), + Val("len(ai[1:])", 1), + Val("len(ai[2:])", 0), Val("len(aai)", 2), Val("len(sli)", 2), + Val("len(sli[0:])", 2), + Val("len(sli[1:])", 1), + Val("len(sli[2:])", 0), // TODO(austin) Test len of map CErr("len(0)", opTypes), CErr("len(i)", opTypes), |