# Is it possible to write something like:\`\`\`op = :(&&)set = AndSet@eval f

**URL:** https://discourse.julialang.org/t/is-it-possible-to-write-something-like-op-amp-amp-set-andset-eval-f/57417
**Category:** General Usage
**Created:** [March 17, 2021, 9:23pm UTC](https://discourse.julialang.org/t/is-it-possible-to-write-something-like-op-amp-amp-set-andset-eval-f/57417 "2021-03-17T21:23:43Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![BridgeBot](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/bridgebot/32/21491_2.png) [@BridgeBot](https://discourse.julialang.org/u/BridgeBot)
#### Post date: [March 17, 2021, 9:23pm UTC](https://discourse.julialang.org/t/is-it-possible-to-write-something-like-op-amp-amp-set-andset-eval-f/57417/1 "2021-03-17T21:23:43Z")

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is it possible to write something like:

```julia
op = :(&&)
set = AndSet
@eval do_some_operation(::$set, lhs, rhs) = lhs $op $rhs

```

? The `$op` part does not get parsed as hoped. Any way to rewrite this to make it possible?

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### Author: ![Wikunia](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/wikunia/32/2180_2.png) [@Wikunia](https://discourse.julialang.org/u/Wikunia)
#### Post date: [March 17, 2021, 10:04pm UTC](https://discourse.julialang.org/t/is-it-possible-to-write-something-like-op-amp-amp-set-andset-eval-f/57417/2 "2021-03-17T22:04:51Z")

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Answered by @simeonschaub on Slack

```julia
@eval do_some_operation(::$(set), lhs, rhs) = $(Expr(op, :lhs, :rhs))

```

works and for things like `\xor` one needs to write

```julia
@eval do_some_operation(::$(set), lhs, rhs) = $(Expr(:call, op, :lhs, :rhs))

```

or simply `$op(lhs, rhs)`