Python

migen
A Python toolbox for building complex digital hardware

MyHDL
Python as a hardware description and verification language

nMigen
A refreshed Python toolbox for building complex digital hardware

PipelineC
Open source C-like hardware description language with high-level-synthesis-like automatic pipelining and several other real life design inspired features.

pyFPGA
A Python package to use FPGA development tools programmatically

pyVHDLModel
An abstract language model of VHDL written in Python