Pass texture array to shader

Hi, I’m working on compute shader and try to pass a texture array to hlsl, what i’ve done is something like:

//shader parameters defined in Sub FGlobalShader class
        SHADER_PARAMETER_ARRAY(FMatrix, Transforms, [10])
        SHADER_PARAMETER_RDG_TEXTURE_ARRAY(Texture2D, Textures, [10])
        SHADER_PARAMETER_SAMPLER(SamplerState, SceneTextureSampler)

and in .usf:

Texture2D<float4> Textures[10];
float4x4 Transforms[10];

But it can’t complete the compile with an error shown:

permutation 0 has unbound parameters not represented in the parameter struct:

So i dive in to engine source and see how they use them, it shows like that:

Texture2D<float4> Textures_0;
Texture2D<float4> Textures_1;

I’ve tried and it works fine, so my question is why float4x4 Transforms[10]; is acceptable but for texture is not? and the syntax of Textures_0 is a little strange, any theories?
My engine version is 4.27.2, dx11.