diff options
| -rw-r--r-- | docs/content/3.manual/manual.yml | 10 | ||||
| -rw-r--r-- | parser.y | 4 | ||||
| -rw-r--r-- | tests/all.test | 8 |
3 files changed, 22 insertions, 0 deletions
diff --git a/docs/content/3.manual/manual.yml b/docs/content/3.manual/manual.yml index 4d3ac45f..973e8d85 100644 --- a/docs/content/3.manual/manual.yml +++ b/docs/content/3.manual/manual.yml @@ -1584,6 +1584,16 @@ sections: input: 'true' output: ['"some exception"'] + - title: `?` operator + body: | + + The `?` operator, used as `EXP?`, is shorthand for `try EXP`. + + examples: + - program: '[.[]|(.a)?]' + input: '[{}, true, {"a":1}' + output: ['[null, 1]'] + - title: Advanced features body: | Variables are an absolute necessity in most programming languages, but @@ -255,6 +255,10 @@ Term "as" '$' IDENT '|' Exp { $$ = $2; } | +Exp '?' { + $$ = gen_try($1, gen_op_simple(BACKTRACK)); +} | + Exp '=' Exp { $$ = gen_call("_assign", BLOCK(gen_lambda($1), gen_lambda($3))); diff --git a/tests/all.test b/tests/all.test index f5c7bd68..4bd15cee 100644 --- a/tests/all.test +++ b/tests/all.test @@ -670,6 +670,14 @@ def inc(x): x |= .+1; inc(.[].a) [0,1,2,3] ["foo","Cannot index number with string \"a\"",3] +[.[]|(.a, .a)?] +[null,true,{"a":1}] +[null,null,1,1] + +[[.[]|[.a,.a]]?] +[null,true,{"a":1}] +[] + # string operations [.[]|startswith("foo")] ["fo", "foo", "barfoo", "foobar", "barfoob"] |