|  | error: unexpected token: $ | 
|  | --> $DIR/syntax-errors.rs:9:8 | 
|  | | | 
|  | LL |     ( $$ $a:ident ) => { | 
|  | |        ^ | 
|  |  | 
|  | note: `$$` and meta-variable expressions are not allowed inside macro parameter definitions | 
|  | --> $DIR/syntax-errors.rs:9:8 | 
|  | | | 
|  | LL |     ( $$ $a:ident ) => { | 
|  | |        ^ | 
|  |  | 
|  | error: unexpected token: { | 
|  | --> $DIR/syntax-errors.rs:15:8 | 
|  | | | 
|  | LL |     ( ${ len() } ) => { | 
|  | |        ^^^^^^^^^ | 
|  |  | 
|  | note: `$$` and meta-variable expressions are not allowed inside macro parameter definitions | 
|  | --> $DIR/syntax-errors.rs:15:8 | 
|  | | | 
|  | LL |     ( ${ len() } ) => { | 
|  | |        ^^^^^^^^^ | 
|  |  | 
|  | error: expected one of: `*`, `+`, or `?` | 
|  | --> $DIR/syntax-errors.rs:15:8 | 
|  | | | 
|  | LL |     ( ${ len() } ) => { | 
|  | |        ^^^^^^^^^ | 
|  |  | 
|  | error: meta-variables within meta-variable expressions must be referenced using a dollar sign | 
|  | --> $DIR/syntax-errors.rs:22:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ ignore() } }; | 
|  | |                                 ^^^^^^ | 
|  |  | 
|  | error: only unsuffixes integer literals are supported in meta-variable expressions | 
|  | --> $DIR/syntax-errors.rs:27:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ index(1u32) } }; | 
|  | |                                 ^^^^^ | 
|  |  | 
|  | error: expected `(` | 
|  | --> $DIR/syntax-errors.rs:32:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ count } }; | 
|  | |                                 ^^^^^- help: try adding parentheses: `( /* ... */ )` | 
|  | |                                 | | 
|  | |                                 for this this metavariable expression | 
|  | | | 
|  | = note: metavariable expressions use function-like parentheses syntax | 
|  |  | 
|  | error: expected `(` | 
|  | --> $DIR/syntax-errors.rs:49:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ count $i ($i) } }; | 
|  | |                                 ^^^^^ - unexpected token | 
|  | |                                 | | 
|  | |                                 for this this metavariable expression | 
|  | | | 
|  | = note: metavariable expressions use function-like parentheses syntax | 
|  |  | 
|  | error: expected `(` | 
|  | --> $DIR/syntax-errors.rs:54:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ count{i} } }; | 
|  | |                                 ^^^^^ for this this metavariable expression | 
|  | | | 
|  | = note: metavariable expressions use function-like parentheses syntax | 
|  |  | 
|  | error: expected identifier, found `123` | 
|  | --> $DIR/syntax-errors.rs:59:23 | 
|  | | | 
|  | LL |     () => { ${ignore($123)} } | 
|  | |                       ^^^ help: try removing `123` | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:71:19 | 
|  | | | 
|  | LL |         ${count() a b c} | 
|  | |           -----   ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:73:20 | 
|  | | | 
|  | LL |         ${count($i a b c)} | 
|  | |           -----    ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  | | | 
|  | = note: the `count` metavariable expression takes between 1 and 2 arguments | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:75:23 | 
|  | | | 
|  | LL |         ${count($i, 1 a b c)} | 
|  | |           -----       ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  | | | 
|  | = note: the `count` metavariable expression takes between 1 and 2 arguments | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:77:21 | 
|  | | | 
|  | LL |         ${count($i) a b c} | 
|  | |           -----     ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:80:22 | 
|  | | | 
|  | LL |         ${ignore($i) a b c} | 
|  | |           ------     ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:82:21 | 
|  | | | 
|  | LL |         ${ignore($i a b c)} | 
|  | |           ------    ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  | | | 
|  | = note: the `ignore` metavariable expression takes a single argument | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:85:19 | 
|  | | | 
|  | LL |         ${index() a b c} | 
|  | |           -----   ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:87:19 | 
|  | | | 
|  | LL |         ${index(1 a b c)} | 
|  | |           -----   ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  | | | 
|  | = note: the `index` metavariable expression takes between 0 and 1 arguments | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:90:19 | 
|  | | | 
|  | LL |         ${index() a b c} | 
|  | |           -----   ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:92:19 | 
|  | | | 
|  | LL |         ${index(1 a b c)} | 
|  | |           -----   ^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  | | | 
|  | = note: the `index` metavariable expression takes between 0 and 1 arguments | 
|  |  | 
|  | error: unexpected trailing tokens | 
|  | --> $DIR/syntax-errors.rs:94:18 | 
|  | | | 
|  | LL |         ${index(1, a b c)} | 
|  | |           -----  ^^^^^^^ help: try removing these tokens | 
|  | |           | | 
|  | |           for this metavariable expression | 
|  | | | 
|  | = note: the `index` metavariable expression takes between 0 and 1 arguments | 
|  |  | 
|  | error: meta-variable expression depth must be a literal | 
|  | --> $DIR/syntax-errors.rs:101:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ index(IDX) } }; | 
|  | |                                 ^^^^^ | 
|  |  | 
|  | error: meta-variables within meta-variable expressions must be referenced using a dollar sign | 
|  | --> $DIR/syntax-errors.rs:107:11 | 
|  | | | 
|  | LL |         ${count(foo)} | 
|  | |           ^^^^^ | 
|  |  | 
|  | error: meta-variables within meta-variable expressions must be referenced using a dollar sign | 
|  | --> $DIR/syntax-errors.rs:114:11 | 
|  | | | 
|  | LL |         ${ignore(bar)} | 
|  | |           ^^^^^^ | 
|  |  | 
|  | error: unrecognized metavariable expression | 
|  | --> $DIR/syntax-errors.rs:120:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ aaaaaaaaaaaaaa(i) } }; | 
|  | |                                 ^^^^^^^^^^^^^^ not a valid metavariable expression | 
|  | | | 
|  | = note: valid metavariable expressions are `count`, `ignore`, `index`, `len`, and `concat` | 
|  |  | 
|  | error: expected identifier or string literal | 
|  | --> $DIR/syntax-errors.rs:38:14 | 
|  | | | 
|  | LL |     () => { ${} }; | 
|  | |              ^^ | 
|  |  | 
|  | error: expected identifier, found `"hi"` | 
|  | --> $DIR/syntax-errors.rs:44:17 | 
|  | | | 
|  | LL |      () => { ${ "hi" } }; | 
|  | |                 ^^^^ help: try removing `"hi"` | 
|  |  | 
|  | error: expected identifier or string literal | 
|  | --> $DIR/syntax-errors.rs:65:33 | 
|  | | | 
|  | LL |     ( $( $i:ident ),* ) => { ${ {} } }; | 
|  | |                                 ^^ | 
|  |  | 
|  | error: aborting due to 27 previous errors | 
|  |  |