# ERROR: LoadError: syntax: invalid identifier name "&&"

**URL:** <https://discourse.julialang.org/t/error-loaderror-syntax-invalid-identifier-name/45034>\
**Category:** General Usage\
**Created:** [August 16, 2020, 10:47am UTC](https://discourse.julialang.org/t/error-loaderror-syntax-invalid-identifier-name/45034 "2020-08-16T10:47:25Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![mamo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mamo/32/25591_2.png) [@mamo](https://discourse.julialang.org/u/mamo)\
**Post date:** [August 16, 2020, 10:47am UTC](https://discourse.julialang.org/t/error-loaderror-syntax-invalid-identifier-name/45034/1 "2020-08-16T10:47:25Z")

</div>

Dear all,  
why it reports error with && in case below:  
sum((change\_cost[k,l,j]\*C[k,l,j,t,t+1]) for k in F, l in F, j in U, t in TIME: (t\<=length(TIME)-1) && (k != l))  
Thanks!

---

<div class="post-metadata">

**Author:** ![tomerarnon](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/tomerarnon/32/3170_2.png) [@tomerarnon](https://discourse.julialang.org/u/tomerarnon)\
**Post date:** [August 16, 2020, 10:50am UTC](https://discourse.julialang.org/t/error-loaderror-syntax-invalid-identifier-name/45034/2 "2020-08-16T10:50:53Z")

</div>

Please [make it easier to help you](https://discourse.julialang.org/t/psa-make-it-easier-to-help-you/14757)

My guess is it has to do with `TIME:`, or with some of those parentheses. Something there is invalid syntax.

---

<div class="post-metadata">

**Author:** ![GunnarFarneback](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/gunnarfarneback/32/1827_2.png) [@GunnarFarneback](https://discourse.julialang.org/u/GunnarFarneback)\
**Post date:** [August 16, 2020, 10:53am UTC](https://discourse.julialang.org/t/error-loaderror-syntax-invalid-identifier-name/45034/3 "2020-08-16T10:53:40Z")

</div>

I’m not exactly sure how it tried to parse it but the problem is almost certainly with `:`, where you probably want `if` instead.

---

<div class="post-metadata">

**Author:** ![mamo](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/mamo/32/25591_2.png) [@mamo](https://discourse.julialang.org/u/mamo)\
**Post date:** [August 16, 2020, 10:55am UTC](https://discourse.julialang.org/t/error-loaderror-syntax-invalid-identifier-name/45034/4 "2020-08-16T10:55:46Z")

</div>

great, **if** is the solution.  
Thank you both.