EC_NODE_EXPR_EVAL(3)

💖 EC_NODE_EXPR_EVAL(3) — bestie edition 💖

okay so real quick, this is a page straight out of the Libecoli Programmer's Manual, and it's about one very specific little function. let's get into it ✨

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🌸 NAME 🌸

ec_node_expr_eval — Evaluate a parsed expression.

like. it evaluates. a parsed expression. that's the whole job bestie 💅

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✨ SYNOPSIS ✨

first you gotta pull in the header, obvs:

#include <ecoli/node_expr.h>

and here's the function signature in all its glory — comments and everything, no cap:

int ec_node_expr_eval(
    /*
     * On success, this pointer will be set to the evaluated result.
     */
    void                                **result,
    const struct ec_node                 *node,     /* The expression node. */
    struct ec_pnode                      *parse,    /* The parse tree to evaluate. */
    const struct ec_node_expr_eval_ops   *ops,      /* The evaluation callbacks. */
    void                                 *userctx   /* A user-defined context passed to all callbacks. */
);

so result is where the evaluated answer lands when everything goes right, node is your expression node, parse is the parse tree you're evaluating, ops is your bundle of evaluation callbacks, and userctx is whatever lil context you want passed along to every single callback 🫶

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🎀 STRUCTURES 🎀

Expression evaluation operations.

the ops struct. the moment. here it is, literally exactly as written:

struct ec_node_expr_eval_ops {
};

yes it's empty. that's the whole struct. it's giving minimalist, it's giving "we'll fill this in later," it is what it is 💀

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🔥 RETURN VALUE 🔥

• 0 on success 🎉
• -1 on error, and errno is set so you can go find out what went wrong 😭

periodt.

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👑 SEE ALSO 👑

go read these next, they're all part of the same friend group:

• ec_node_expr_set_val_node(3)
• ec_node_expr_add_bin_op(3)
• ec_node_expr(3)
• ec_node_expr_add_pre_op(3)
• ec_node_expr_add_parenthesis(3)
• ec_node_expr_add_post_op(3)

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💜 COPYRIGHT 💜

Copyright (C) 2010-2026 Olivier Matz, Robin Jarry.

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and that's the whole page bestie, tysm for reading 🦋 mwah 💋

signing off with love from libecoli, dated 2026-06-11 — it's giving iconic, it's giving timeless, it's giving EC_NODE_EXPR_EVAL(3) 💅✨