Can't use logical operators in handlebars #if statement?
I have the following code:
{{#if true}} An {{else}} A {{/if}
That's the entire template. It's loading fine. But notice the #if condition is simply true. If I put anything other than a literal there, it doesn't work. Any variable I put any sort of programmatic expression like {{#if 3 > 5}}, it gives me a Parser Error:
Error: Parse error on line 36:
{{#if 3 > 5 }} An {{else}} A
---------------------^
Expecting 'CLOSE_RAW_BLOCK', 'CLOSE', 'CLOSE_UNESCAPED', 'OPEN_SEXPR', 'CLOSE_SEXPR', 'ID', 'OPEN_BLOCK_PARAMS', 'STRING', 'NUMBER', 'BOOLEAN', 'UNDEFINED', 'NULL', 'DATA', got 'INVALID'
I can't figure that out. I even reduced it to just {{#if 3 > 5}} A {{/if}} and it still gives a parser error.
So I thought maybe you have to use a helper for this sort of thing, but I can't get any helper I register to work either.
handlebars.js
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
add a comment |
I have the following code:
{{#if true}} An {{else}} A {{/if}
That's the entire template. It's loading fine. But notice the #if condition is simply true. If I put anything other than a literal there, it doesn't work. Any variable I put any sort of programmatic expression like {{#if 3 > 5}}, it gives me a Parser Error:
Error: Parse error on line 36:
{{#if 3 > 5 }} An {{else}} A
---------------------^
Expecting 'CLOSE_RAW_BLOCK', 'CLOSE', 'CLOSE_UNESCAPED', 'OPEN_SEXPR', 'CLOSE_SEXPR', 'ID', 'OPEN_BLOCK_PARAMS', 'STRING', 'NUMBER', 'BOOLEAN', 'UNDEFINED', 'NULL', 'DATA', got 'INVALID'
I can't figure that out. I even reduced it to just {{#if 3 > 5}} A {{/if}} and it still gives a parser error.
So I thought maybe you have to use a helper for this sort of thing, but I can't get any helper I register to work either.
handlebars.js
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
add a comment |
I have the following code:
{{#if true}} An {{else}} A {{/if}
That's the entire template. It's loading fine. But notice the #if condition is simply true. If I put anything other than a literal there, it doesn't work. Any variable I put any sort of programmatic expression like {{#if 3 > 5}}, it gives me a Parser Error:
Error: Parse error on line 36:
{{#if 3 > 5 }} An {{else}} A
---------------------^
Expecting 'CLOSE_RAW_BLOCK', 'CLOSE', 'CLOSE_UNESCAPED', 'OPEN_SEXPR', 'CLOSE_SEXPR', 'ID', 'OPEN_BLOCK_PARAMS', 'STRING', 'NUMBER', 'BOOLEAN', 'UNDEFINED', 'NULL', 'DATA', got 'INVALID'
I can't figure that out. I even reduced it to just {{#if 3 > 5}} A {{/if}} and it still gives a parser error.
So I thought maybe you have to use a helper for this sort of thing, but I can't get any helper I register to work either.
handlebars.js
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
I have the following code:
{{#if true}} An {{else}} A {{/if}
That's the entire template. It's loading fine. But notice the #if condition is simply true. If I put anything other than a literal there, it doesn't work. Any variable I put any sort of programmatic expression like {{#if 3 > 5}}, it gives me a Parser Error:
Error: Parse error on line 36:
{{#if 3 > 5 }} An {{else}} A
---------------------^
Expecting 'CLOSE_RAW_BLOCK', 'CLOSE', 'CLOSE_UNESCAPED', 'OPEN_SEXPR', 'CLOSE_SEXPR', 'ID', 'OPEN_BLOCK_PARAMS', 'STRING', 'NUMBER', 'BOOLEAN', 'UNDEFINED', 'NULL', 'DATA', got 'INVALID'
I can't figure that out. I even reduced it to just {{#if 3 > 5}} A {{/if}} and it still gives a parser error.
So I thought maybe you have to use a helper for this sort of thing, but I can't get any helper I register to work either.
handlebars.js
handlebars.js
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
edited Nov 29 '18 at 3:47
temporary_user_name
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
asked Nov 24 '18 at 21:31
temporary_user_nametemporary_user_name
16.8k2997163
16.8k2997163
add a comment |
add a comment |
1 Answer
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Turns out the #if helper can only test for properties to be true or false – not arbitrary expressions[source], so you have to do everything with helpers. Just write a function to compare things with logical operators and return true or false.
And to save you some trouble, the syntax for calling helpers doesn't use parentheses, either....arguments are space-separated like in rails. So it looks like:
{{myHelperFunction myarg1 myarg2}}
And if you want to nest helpers, you need parens:
{{myOuterHelper (myInnerHelper myarg1 myarg2)}}
Last tip from me, if you want to nest your helper with an #if, you need parens, too:
{{#if (myHelper myarg1 myarg2)}} content {{/if}}
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Turns out the #if helper can only test for properties to be true or false – not arbitrary expressions[source], so you have to do everything with helpers. Just write a function to compare things with logical operators and return true or false.
And to save you some trouble, the syntax for calling helpers doesn't use parentheses, either....arguments are space-separated like in rails. So it looks like:
{{myHelperFunction myarg1 myarg2}}
And if you want to nest helpers, you need parens:
{{myOuterHelper (myInnerHelper myarg1 myarg2)}}
Last tip from me, if you want to nest your helper with an #if, you need parens, too:
{{#if (myHelper myarg1 myarg2)}} content {{/if}}
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
add a comment |
Turns out the #if helper can only test for properties to be true or false – not arbitrary expressions[source], so you have to do everything with helpers. Just write a function to compare things with logical operators and return true or false.
And to save you some trouble, the syntax for calling helpers doesn't use parentheses, either....arguments are space-separated like in rails. So it looks like:
{{myHelperFunction myarg1 myarg2}}
And if you want to nest helpers, you need parens:
{{myOuterHelper (myInnerHelper myarg1 myarg2)}}
Last tip from me, if you want to nest your helper with an #if, you need parens, too:
{{#if (myHelper myarg1 myarg2)}} content {{/if}}
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
add a comment |
Turns out the #if helper can only test for properties to be true or false – not arbitrary expressions[source], so you have to do everything with helpers. Just write a function to compare things with logical operators and return true or false.
And to save you some trouble, the syntax for calling helpers doesn't use parentheses, either....arguments are space-separated like in rails. So it looks like:
{{myHelperFunction myarg1 myarg2}}
And if you want to nest helpers, you need parens:
{{myOuterHelper (myInnerHelper myarg1 myarg2)}}
Last tip from me, if you want to nest your helper with an #if, you need parens, too:
{{#if (myHelper myarg1 myarg2)}} content {{/if}}
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
Turns out the #if helper can only test for properties to be true or false – not arbitrary expressions[source], so you have to do everything with helpers. Just write a function to compare things with logical operators and return true or false.
And to save you some trouble, the syntax for calling helpers doesn't use parentheses, either....arguments are space-separated like in rails. So it looks like:
{{myHelperFunction myarg1 myarg2}}
And if you want to nest helpers, you need parens:
{{myOuterHelper (myInnerHelper myarg1 myarg2)}}
Last tip from me, if you want to nest your helper with an #if, you need parens, too:
{{#if (myHelper myarg1 myarg2)}} content {{/if}}
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
edited Nov 28 '18 at 4:19
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
answered Nov 24 '18 at 22:07
temporary_user_nametemporary_user_name
16.8k2997163
16.8k2997163
add a comment |
add a comment |
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