# JuMP raw expr input

**URL:** <https://discourse.julialang.org/t/jump-raw-expr-input/101795>\
**Category:** Optimization (Mathematical)\
**Created:** [July 19, 2023, 5:16pm UTC](https://discourse.julialang.org/t/jump-raw-expr-input/101795 "2023-07-19T17:16:40Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![slwu89](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/slwu89/32/217323_2.png) [@slwu89](https://discourse.julialang.org/u/slwu89)\
**Post date:** [July 19, 2023, 5:16pm UTC](https://discourse.julialang.org/t/jump-raw-expr-input/101795/1 "2023-07-19T17:16:40Z")

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Hi all, as far as I can see, raw `Expr` input is only supported for nonlinear expressions ([Nonlinear Modeling · JuMP](https://jump.dev/JuMP.jl/stable/manual/nlp/#Raw-expression-input)), is there some reason why it is not allowed for affine expressions?

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<div class="post-metadata">

**Author:** ![odow](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/odow/32/28685_2.png) [@odow](https://discourse.julialang.org/u/odow)\
**Post date:** [July 20, 2023, 2:15pm UTC](https://discourse.julialang.org/t/jump-raw-expr-input/101795/2 "2023-07-20T14:15:18Z")

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> is there some reason why it is not allowed for affine expressions?

Because you can construct affine expressions via overloading (`2 * x + 1`), there’s no need for manually constructing an `Expr`.

What are you trying to achieve?